/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF5.  The full HDF5 copyright notice, including     *
 * terms governing use, modification, and redistribution, is contained in    *
 * the COPYING file, which can be found at the root of the source code       *
 * distribution tree, or in https://www.hdfgroup.org/licenses.               *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Read-Only S3 Virtual File Driver (VFD)
 *
 * Purpose:    Unit tests for the S3 Communications (s3comms) module.
 */

#include "h5test.h"
#include "H5FDs3comms.h"
#include "H5MMprivate.h" /* memory management */

#ifdef H5_HAVE_ROS3_VFD

/*****************************************************************************
 *
 * FILE-LOCAL TESTING MACROS
 *
 * Purpose:
 *
 *     1) Upon test failure, goto-jump to single-location teardown in test
 *        function. E.g., `error:` (consistency with HDF corpus) or
 *        `failed:` (reflects purpose).
 *            >>> using "error", in part because `H5E_BEGIN_TRY` expects it.
 *     2) Increase clarity and reduce overhead found with `TEST_ERROR`.
 *        e.g., "if(somefunction(arg, arg2) < 0) TEST_ERROR:"
 *        requires reading of entire line to know whether this if/call is
 *        part of the test setup, test operation, or a test unto itself.
 *     3) Provide testing macros with optional user-supplied failure message;
 *        if not supplied (NULL), generate comparison output in the spirit of
 *        test-driven development. E.g., "expected 5 but was -3"
 *        User messages clarify test's purpose in code, encouraging description
 *        without relying on comments.
 *     4) Configurable expected-actual order in generated comparison strings.
 *        Some prefer `VERIFY(expected, actual)`, others
 *        `VERIFY(actual, expected)`. Provide preprocessor ifdef switch
 *        to satisfy both parties, assuming one paradigm per test file.
 *        (One could #undef and redefine the flag through the file as desired,
 *         but _why_.)
 *        Provided as courtesy, per consideration for inclusion in the library
 *        proper.
 *
 *     Macros:
 *
 *         JSVERIFY_EXP_ACT - ifdef flag, configures comparison order
 *         FAIL_IF()        - check condition
 *         FAIL_UNLESS()    - check _not_ condition
 *         JSVERIFY()       - long-int equality check; prints reason/comparison
 *         JSVERIFY_NOT()   - long-int inequality check; prints
 *         JSVERIFY_STR()   - string equality check; prints
 *
 *****************************************************************************/

/*----------------------------------------------------------------------------
 *
 * ifdef flag: JSVERIFY_EXP_ACT
 *
 * JSVERIFY macros accept arguments as (EXPECTED, ACTUAL[, reason])
 *   default, if this is undefined, is (ACTUAL, EXPECTED[, reason])
 *
 *----------------------------------------------------------------------------
 */
#define JSVERIFY_EXP_ACT 1L

/*----------------------------------------------------------------------------
 *
 * Macro: JSFAILED_AT()
 *
 * Purpose:
 *
 *     Preface a test failure by printing "*FAILED*" and location to stdout
 *     Similar to `H5_FAILED(); AT();` from h5test.h
 *
 *     *FAILED* at somefile.c:12 in function_name()...
 *
 *----------------------------------------------------------------------------
 */
#define JSFAILED_AT()                                                                                        \
    {                                                                                                        \
        printf("*FAILED* at %s:%d in %s()...\n", __FILE__, __LINE__, __func__);                              \
    }

/*----------------------------------------------------------------------------
 *
 * Macro: FAIL_IF()
 *
 * Purpose:
 *
 *     Make tests more accessible and less cluttered than
 *         `if (thing == otherthing()) TEST_ERROR`
 *         paradigm.
 *
 *     The following lines are roughly equivalent:
 *
 *         `if (myfunc() < 0) TEST_ERROR;` (as seen elsewhere in HDF tests)
 *         `FAIL_IF(myfunc() < 0)`
 *
 *     Prints a generic "FAILED AT" line to stdout and jumps to `error`,
 *     similar to `TEST_ERROR` in h5test.h
 *
 *----------------------------------------------------------------------------
 */
#define FAIL_IF(condition)                                                                                   \
    if (condition) {                                                                                         \
        JSFAILED_AT()                                                                                        \
        goto error;                                                                                          \
    }

/*----------------------------------------------------------------------------
 *
 * Macro: FAIL_UNLESS()
 *
 * Purpose:
 *
 *     TEST_ERROR wrapper to reduce cognitive overhead from "negative tests",
 *     e.g., "a != b".
 *
 *     Opposite of FAIL_IF; fails if the given condition is _not_ true.
 *
 *     `FAIL_IF( 5 != my_op() )`
 *     is equivalent to
 *     `FAIL_UNLESS( 5 == my_op() )`
 *     However, `JSVERIFY(5, my_op(), "bad return")` may be even clearer.
 *         (see JSVERIFY)
 *
 *----------------------------------------------------------------------------
 */
#define FAIL_UNLESS(condition)                                                                               \
    if (!(condition)) {                                                                                      \
        JSFAILED_AT()                                                                                        \
        goto error;                                                                                          \
    }

/*----------------------------------------------------------------------------
 *
 * Macro: JSERR_LONG()
 *
 * Purpose:
 *
 *     Print an failure message for long-int arguments.
 *     ERROR-AT printed first.
 *     If `reason` is given, it is printed on own line and newlined after
 *     else, prints "expected/actual" aligned on own lines.
 *
 *     *FAILED* at myfile.c:488 in somefunc()...
 *     forest must be made of trees.
 *
 *     or
 *
 *     *FAILED* at myfile.c:488 in somefunc()...
 *       ! Expected 425
 *       ! Actual   3
 *
 *----------------------------------------------------------------------------
 */
static inline void
jserr_long(long expected, long actual, const char *reason)
{
    if (reason != NULL) {
        printf("%s\n", reason);
    }
    else {
        printf("  ! Expected %ld\n  ! Actual   %ld\n", expected, actual);
    }
}

#define JSERR_LONG(expected, actual, reason)                                                                 \
    {                                                                                                        \
        JSFAILED_AT()                                                                                        \
        jserr_long((long)(expected), (long)(actual), reason);                                                \
    }

/*----------------------------------------------------------------------------
 *
 * Macro: JSERR_STR()
 *
 * Purpose:
 *
 *     Print an failure message for string arguments.
 *     ERROR-AT printed first.
 *     If `reason` is given, it is printed on own line and newlined after
 *     else, prints "expected/actual" aligned on own lines.
 *
 *     *FAILED*  at myfile.c:421 in myfunc()...
 *     Blue and Red strings don't match!
 *
 *     or
 *
 *     *FAILED*  at myfile.c:421 in myfunc()...
 *     !!! Expected:
 *     this is my expected
 *     string
 *     !!! Actual:
 *     not what I expected at all
 *
 *----------------------------------------------------------------------------
 */
static inline void
jserr_str(const char *expected, const char *actual, const char *reason)
{
    if (reason != NULL) {
        printf("%s\n", reason);
    }
    else {
        printf("!!! Expected:\n%s\n!!!Actual:\n%s\n", expected, actual);
    }
}

#define JSERR_STR(expected, actual, reason)                                                                  \
    {                                                                                                        \
        JSFAILED_AT()                                                                                        \
        jserr_str((expected), (actual), (reason));                                                           \
    }

#ifdef JSVERIFY_EXP_ACT
/* VERIFY routines with parameter order (<expected>, <actual> [, <msg> ])
 */

/*----------------------------------------------------------------------------
 *
 * Macro: JSVERIFY()
 *
 * Purpose:
 *
 *     Verify that two long integers are equal.
 *     If unequal, print failure message
 *     (with `reason`, if not NULL; expected/actual if NULL)
 *     and jump to `error` at end of function
 *
 *----------------------------------------------------------------------------
 */
#define JSVERIFY(expected, actual, reason)                                                                   \
    if ((long)(actual) != (long)(expected)) {                                                                \
        JSERR_LONG((expected), (actual), (reason))                                                           \
        goto error;                                                                                          \
    } /* JSVERIFY */

#if 0 /* UNUSED */

/*----------------------------------------------------------------------------
 *
 * Macro: JSVERIFY_NOT()
 *
 * Purpose:
 *
 *     Verify that two long integers are _not_ equal.
 *     If equal, print failure message
 *     (with `reason`, if not NULL; expected/actual if NULL)
 *     and jump to `error` at end of function
 *
 *----------------------------------------------------------------------------
 */
#define JSVERIFY_NOT(expected, actual, reason)                                                               \
    if ((long)(actual) == (long)(expected)) {                                                                \
        JSERR_LONG((expected), (actual), (reason))                                                           \
        goto error;                                                                                          \
    }  /* JSVERIFY_NOT */
#endif /* JSVERIFY_NOT unused */

/*----------------------------------------------------------------------------
 *
 * Macro: JSVERIFY_STR()
 *
 * Purpose:
 *
 *     Verify that two strings are equal.
 *     If unequal, print failure message
 *     (with `reason`, if not NULL; expected/actual if NULL)
 *     and jump to `error` at end of function
 *
 *----------------------------------------------------------------------------
 */
#define JSVERIFY_STR(expected, actual, reason)                                                               \
    if (strcmp((actual), (expected)) != 0) {                                                                 \
        JSERR_STR((expected), (actual), (reason));                                                           \
        goto error;                                                                                          \
    } /* JSVERIFY_STR */

#else
/* JSVERIFY_EXP_ACT not defined
 *
 * Repeats macros above, but with actual/expected parameters reversed.
 */

/*----------------------------------------------------------------------------
 * Macro: JSVERIFY()
 * See: JSVERIFY documentation above.
 *----------------------------------------------------------------------------
 */
#define JSVERIFY(actual, expected, reason)                                                                   \
    if ((long)(actual) != (long)(expected)) {                                                                \
        JSERR_LONG((expected), (actual), (reason));                                                          \
        goto error;                                                                                          \
    } /* JSVERIFY */

#if 0 /* UNUSED */

/*----------------------------------------------------------------------------
 * Macro: JSVERIFY_NOT()
 * See: JSVERIFY_NOT documentation above.
 *----------------------------------------------------------------------------
 */
#define JSVERIFY_NOT(actual, expected, reason)                                                               \
    if ((long)(actual) == (long)(expected)) {                                                                \
        JSERR_LONG((expected), (actual), (reason))                                                           \
        goto error;                                                                                          \
    }  /* JSVERIFY_NOT */
#endif /* JSVERIFY_NOT unused */

/*----------------------------------------------------------------------------
 * Macro: JSVERIFY_STR()
 * See: JSVERIFY_STR documentation above.
 *----------------------------------------------------------------------------
 */
#define JSVERIFY_STR(actual, expected, reason)                                                               \
    if (strcmp((actual), (expected)) != 0) {                                                                 \
        JSERR_STR((expected), (actual), (reason));                                                           \
        goto error;                                                                                          \
    } /* JSVERIFY_STR */

#endif /* ifdef/else JSVERIFY_EXP_ACT */

#define S3_TEST_PROFILE_NAME "ros3_vfd_test"

#define S3_TEST_RESOURCE_TEXT_RESTRICTED "t8.shakespeare.txt"
#define S3_TEST_RESOURCE_TEXT_PUBLIC     "Poe_Raven.txt"
#define S3_TEST_RESOURCE_MISSING         "missing.csv"

#define S3_TEST_RUN_TIMEOUT  0   /* run tests that might hang */
#define S3_TEST_MAX_URL_SIZE 256 /* char array size */

/* Global variables for aws test profile.
 * An attempt is made to read ~/.aws/credentials and ~/.aws/config upon test
 * startup -- if unable to open either file or cannot load region, id, and key,
 * tests connecting with S3 will not be run
 */
static int  s3_test_credentials_loaded               = 0;
static char s3_test_aws_region[16]                   = "";
static char s3_test_aws_access_key_id[64]            = "";
static char s3_test_aws_secret_access_key[128]       = "";
static char s3_test_aws_security_token[1024]         = "";
static char s3_test_bucket_url[S3_TEST_MAX_URL_SIZE] = "";
static bool s3_test_bucket_defined                   = false;

/*---------------------------------------------------------------------------
 *
 * Function: test_macro_format_credential()
 *
 * Purpose:
 *
 *     Demonstrate that the macro `S3COMMS_FORMAT_CREDENTIAL`
 *     performs as expected.
 *
 *----------------------------------------------------------------------------
 */
static herr_t
test_macro_format_credential(void)
{
    /************************
     * test-local variables *
     ************************/

    char       dest[256];
    const char access[]   = "AKIAIOSFODNN7EXAMPLE";
    const char date[]     = "20130524";
    const char region[]   = "us-east-1";
    const char service[]  = "s3";
    const char expected[] = "AKIAIOSFODNN7EXAMPLE/20130524/us-east-1/s3/aws4_request";

    TESTING("test_macro_format_credential");

    FAIL_IF(S3COMMS_MAX_CREDENTIAL_SIZE < S3COMMS_FORMAT_CREDENTIAL(dest, access, date, region, service))

    JSVERIFY_STR(expected, dest, NULL)

    PASSED();
    return 0;

error:
    return -1;

} /* end test_macro_format_credential() */

/*---------------------------------------------------------------------------
 *
 * Function: test_aws_canonical_request()
 *
 * Purpose:
 *
 *     Demonstrate the construction of a Canonical Request (and Signed Headers)
 *
 *     Elided / not yet implemented:
 *         Query strings
 *         request "body"
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_aws_canonical_request(void)
{
    /*************************
     * test-local structures *
     *************************/

    struct header {
        const char *name;
        const char *value;
    };

    struct testcase {
        const char   *exp_request;
        const char   *exp_headers;
        const char   *verb;
        const char   *resource;
        unsigned int  listsize;
        struct header list[5];
    };

    /************************
     * test-local variables *
     ************************/

    struct testcase cases[] = {
        {
            "GET\n/some/"
            "path.file\n\nhost:somebucket.someserver.somedomain\nrange:bytes=150-244\n\nhost;"
            "range\ne3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
            "host;range",
            "GET",
            "/some/path.file",
            2,
            {
                {"Range", "bytes=150-244"},
                {"Host", "somebucket.someserver.somedomain"},
            },
        },
        {"HEAD\n/bucketpath/"
         "myfile.dat\n\nhost:place.domain\nx-amz-content-sha256:"
         "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855\nx-amz-date:"
         "19411207T150803Z\n\nhost;x-amz-content-sha256;x-amz-"
         "date\ne3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
         "host;x-amz-content-sha256;x-amz-date",
         "HEAD",
         "/bucketpath/myfile.dat",
         3,
         {
             {"x-amz-content-sha256", "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"},
             {"host", "place.domain"},
             {"x-amz-date", "19411207T150803Z"},
         }},
        {
            "PUT\n/\n\n\n\ne3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
            "",
            "PUT",
            "/",
            0,
            {
                {"", ""},
            }, /* unused; satisfies compiler */
        },
    }; /* struct testcase cases[] */
    struct testcase *C = NULL;
    char             cr_dest[512];   /* canonical request */
    hrb_t           *hrb     = NULL; /* http request buffer object */
    unsigned int     i       = 0;    /* looping/indexing */
    unsigned int     j       = 0;    /* looping/indexing */
    hrb_node_t      *node    = NULL; /* http headers list pointer */
    unsigned int     n_cases = 3;
    char             sh_dest[64]; /* signed headers */

    TESTING("test_aws_canonical_request");

    for (i = 0; i < n_cases; i++) {
        /* pre-test bookkeeping
         */
        C = &cases[i];
        for (j = 0; j < 256; j++) {
            cr_dest[j] = 0;
        } /* zero request buffer */
        for (j = 0; j < 64; j++) {
            sh_dest[j] = 0;
        } /* zero headers buffer */

        /* create HTTP request object with given verb, resource/path
         */
        hrb = H5FD_s3comms_hrb_init_request(C->verb, C->resource, "HTTP/1.1");
        assert(hrb->body == NULL);

        /* Create headers list from test case input
         */
        for (j = 0; j < C->listsize; j++) {
            FAIL_IF(FAIL == H5FD_s3comms_hrb_node_set(&node, C->list[j].name, C->list[j].value));
        }

        hrb->first_header = node;

        /* test
         */
        JSVERIFY(SUCCEED, H5FD_s3comms_aws_canonical_request(cr_dest, 512, sh_dest, 64, hrb),
                 " unable to compose canonical request")
        JSVERIFY_STR(C->exp_headers, sh_dest, NULL)
        JSVERIFY_STR(C->exp_request, cr_dest, NULL)

        /* tear-down
         */
        while (node != NULL) {
            FAIL_IF(FAIL == H5FD_s3comms_hrb_node_set(&node, node->name, NULL));
        }
        assert(NULL == node);
        FAIL_IF(FAIL == H5FD_s3comms_hrb_destroy(&hrb));
        assert(NULL == hrb);

    } /* for each test case */

    /***************
     * ERROR CASES *
     ***************/

    /*  malformed hrb and/or node-list
     */
    JSVERIFY(FAIL, H5FD_s3comms_aws_canonical_request(cr_dest, 20, sh_dest, 20, NULL),
             "http request object cannot be null")

    hrb = H5FD_s3comms_hrb_init_request("GET", "/", "HTTP/1.1");
    JSVERIFY(FAIL, H5FD_s3comms_aws_canonical_request(NULL, 20, sh_dest, 20, hrb),
             "canonical request destination cannot be NULL")

    JSVERIFY(FAIL, H5FD_s3comms_aws_canonical_request(cr_dest, 20, NULL, 20, hrb),
             "signed headers destination cannot be null")

    FAIL_IF(FAIL == H5FD_s3comms_hrb_destroy(&hrb))
    assert(NULL == hrb);

    PASSED();
    return 0;

error:

    if (node != NULL) {
        while (node != NULL)
            (void)H5FD_s3comms_hrb_node_set(&node, node->name, NULL);
        assert(node == NULL);
    }
    if (hrb != NULL) {
        (void)H5FD_s3comms_hrb_destroy(&hrb);
    }

    return -1;

} /* end test_aws_canonical_request() */

/*---------------------------------------------------------------------------
 *
 * Function: test_bytes_to_hex
 *
 * Purpose:
 *
 *     Define and verify behavior of  `H5FD_s3comms_bytes_to_hex()`.
 *
 * Return:
 *
 *     Success:  0
 *     Failure: -1
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_bytes_to_hex(void)
{
    /*************************
     * test-local structures *
     *************************/

    struct testcase {
        const char          exp[17]; /* in size * 2 + 1 for null terminator */
        const unsigned char in[8];
        size_t              size;
        bool                lower;
    };

    /************************
     * test-local variables *
     ************************/

    struct testcase cases[] = {
        {
            "52F3000C9A",
            {82, 243, 0, 12, 154},
            5,
            false,
        },
        {
            "009a0cf3005200", /* lowercase alphas */
            {0, 154, 12, 243, 0, 82, 0},
            7,
            true,
        },
        {
            "", {17, 63, 26, 56}, 0, false, /* irrelevant */
        },
    };
    int  i       = 0;
    int  n_cases = 3;
    char out[17];
    int  out_off = 0;

    TESTING("bytes-to-hex");

    for (i = 0; i < n_cases; i++) {
        for (out_off = 0; out_off < 17; out_off++) {
            out[out_off] = 0;
        }

        JSVERIFY(SUCCEED, H5FD_s3comms_bytes_to_hex(out, cases[i].in, cases[i].size, cases[i].lower), NULL)

        JSVERIFY_STR(cases[i].exp, out, NULL)
    }

    /* dest cannot be null
     */
    JSVERIFY(FAIL, H5FD_s3comms_bytes_to_hex(NULL, (const unsigned char *)"nada", 5, false),
             "destination cannot be null")

    PASSED();
    return 0;

error:
    return -1;

} /* end test_bytes_to_hex() */

/*---------------------------------------------------------------------------
 *
 * Function: test_hrb_init_request()
 *
 * Purpose:
 *
 *     Define and verify behavior of `H5FD_s3comms_hrb_init_request()`
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_hrb_init_request(void)
{
    /*********************
     * test-local macros *
     *********************/

    /*************************
     * test-local structures *
     *************************/

    struct testcase {
        const char  msg[64];
        const char *verb;
        const char *resource;
        const char *exp_res;
        const char *version;
        bool        ret_null;
    };

    /************************
     * test-local variables *
     ************************/

    struct testcase cases[] = {
        {
            "get HTTP request just as we provided",
            "GET",
            "/path/to/some/file",
            "/path/to/some/file",
            "HTTP/1.1",
            false,
        },
        {
            "null verb substitutes to GET",
            NULL,
            "/MYPATH/MYFILE.tiff",
            "/MYPATH/MYFILE.tiff",
            "HTTP/1.1",
            false,
        },
        {
            "demonstrate non-GET verb",
            "HEAD",
            "/MYPATH/MYFILE.tiff",
            "/MYPATH/MYFILE.tiff",
            "HTTP/1.1",
            false,
        },
        {
            "slash prepended to resource path, if necessary",
            NULL,
            "MYPATH/MYFILE.tiff",
            "/MYPATH/MYFILE.tiff",
            NULL,
            false,
        },
        {
            "null resource path causes problem",
            "GET",
            NULL,
            NULL,
            NULL,
            true,
        },
    };
    struct testcase *C      = NULL;
    unsigned int     i      = 0;
    unsigned int     ncases = 5;
    hrb_t           *req    = NULL;

    TESTING("hrb_init_request");

    for (i = 0; i < ncases; i++) {
        C   = &cases[i];
        req = H5FD_s3comms_hrb_init_request(C->verb, C->resource, C->version);
        if (cases[i].ret_null == true) {
            FAIL_IF(req != NULL);
        }
        else {
            FAIL_IF(req == NULL);
            JSVERIFY(S3COMMS_HRB_MAGIC, req->magic, NULL)
            if (C->verb == NULL) {
                JSVERIFY_STR("GET", req->verb, NULL)
            }
            else {
                JSVERIFY_STR(req->verb, C->verb, NULL)
            }
            JSVERIFY_STR("HTTP/1.1", req->version, NULL)
            JSVERIFY_STR(C->exp_res, req->resource, NULL)
            FAIL_IF(req->first_header != NULL);
            FAIL_IF(req->body != NULL);
            JSVERIFY(0, req->body_len, NULL)
            JSVERIFY(SUCCEED, H5FD_s3comms_hrb_destroy(&req), "unable to destroy hrb_t")
            FAIL_IF(NULL != req); /* should annull pointer as well as free */
        }

    } /* end for each testcase */

    PASSED();
    return 0;

error:
    (void)H5FD_s3comms_hrb_destroy(&req);

    return -1;

} /* end test_hrb_init_request() */

/*---------------------------------------------------------------------------
 *
 * Function: test_hrb_node_set()
 *
 * Purpose:
 *
 *     Test operations on hrb_node_t structure
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_hrb_node_set(void)
{
    /*************************
     * test-local structures *
     *************************/

    /* bundle of name/value representing an hrb_node_t
     */
    typedef struct node_mock_t {
        const char *name;
        const char *value;
    } node_mock_t;

    /* bundle for a testcase
     *
     * `message`
     *     purpose of the testcase
     *
     * `delta`
     *     container for name and value strings to pass into node-set function
     *     to to modify the list.
     *
     * `returned`
     *     expected return value of node-set function
     *
     * `given`
     * `expected`
     *     string arrays representing the state of the list before and after
     *     modification. The number of strings must be even, with each name
     *     paired to a value. `NULL` terminates the list, with `{NULL}`
     *     representing the empty list.
     */
    typedef struct testcase {
        const char *message;
        node_mock_t delta;
        herr_t      returned;
        const char *given[11]; /* name/value pairs in array; NULL sentinel */
        const char *expected[11];
    } testcase;

    /************************
     * test-local variables *
     ************************/

    testcase cases[] = {
        {
            "cannot remove node from null list",
            {"Host", NULL},
            FAIL,
            {NULL},
            {NULL},
        },
        {
            "cannot create list with NULL field name",
            {NULL, "somevalue"},
            FAIL,
            {NULL},
            {NULL},
        },
        {
            "create a new list",
            {"Host", "somevalue"},
            SUCCEED,
            {NULL},
            {
                "Host",
                "somevalue",
                NULL,
            },
        },
        {
            "insert new node at head list",
            {"Host", "somevalue"},
            SUCCEED,
            {
                "Range",
                "bytes=20-40",
                NULL,
            },
            {
                "Host",
                "somevalue",
                "Range",
                "bytes=20-40",
                NULL,
            },
        },
        {
            "append new node at list end",
            {"x-amz-date", "somevalue"},
            SUCCEED,
            {
                "Range",
                "bytes=20-40",
                NULL,
            },
            {
                "Range",
                "bytes=20-40",
                "x-amz-date",
                "somevalue",
                NULL,
            },
        },
        {
            "insert new node inside list",
            {"Intermediary", "somevalue"},
            SUCCEED,
            {
                "Host",
                "somehost",
                "Range",
                "bytes=20-40",
                NULL,
            },
            {
                "Host",
                "somehost",
                "Intermediary",
                "somevalue",
                "Range",
                "bytes=20-40",
                NULL,
            },
        },
        {
            "modify node",
            {"Range", "bytes=40-80"},
            SUCCEED,
            {
                "Host",
                "somehost",
                "Range",
                "bytes=20-40",
                NULL,
            },
            {
                "Host",
                "somehost",
                "Range",
                "bytes=40-80",
                NULL,
            },
        },
        {
            "modify node with new case",
            {"RANGE", "bytes=40-80"},
            SUCCEED,
            {
                "Host",
                "somehost",
                "Range",
                "bytes=20-40",
                NULL,
            },
            {
                "Host",
                "somehost",
                "RANGE",
                "bytes=40-80",
                NULL,
            },
        },
        {
            "cannot add node with no name",
            {NULL, "bytes=40-80"},
            FAIL,
            {
                "Host",
                "somehost",
                NULL,
            },
            {
                "Host",
                "somehost",
                NULL,
            },
        },
        {
            "add node with 'empty' name",
            {"", "bytes=40-80"},
            SUCCEED,
            {
                "Host",
                "somehost",
                NULL,
            },
            {
                "",
                "bytes=40-80",
                "Host",
                "somehost",
                NULL,
            },
        },
        {
            "remove node from end of list",
            {"Host", NULL},
            SUCCEED,
            {
                "Date",
                "Thr, 25 Jan 2018",
                "Host",
                "somehost",
                NULL,
            },
            {
                "Date",
                "Thr, 25 Jan 2018",
                NULL,
            },
        },
        {
            "remove node from middle of list",
            {"Host", NULL},
            SUCCEED,
            {
                "Date",
                "Thr, 25 Jan 2018",
                "Host",
                "somehost",
                "Range",
                "bytes=20-40",
                NULL,
            },
            {
                "Date",
                "Thr, 25 Jan 2018",
                "Range",
                "bytes=20-40",
                NULL,
            },
        },
        {
            "remove node from start of list",
            {"Date", NULL},
            SUCCEED,
            {
                "Date",
                "Thr, 25 Jan 2018",
                "Host",
                "somehost",
                "Range",
                "bytes=20-40",
                NULL,
            },
            {
                "Host",
                "somehost",
                "Range",
                "bytes=20-40",
                NULL,
            },
        },
        {
            "remove only node in list",
            {"Date", NULL},
            SUCCEED,
            {
                "Date",
                "Thr, 25 Jan 2018",
                NULL,
            },
            {
                NULL,
            },
        },
        {
            "attempt to remove absent node fails",
            {"Host", NULL},
            FAIL,
            {
                "Date",
                "Thr, 25 Jan 2018",
                "Range",
                "bytes=20-40",
                NULL,
            },
            {
                "Date",
                "Thr, 25 Jan 2018",
                "Range",
                "bytes=20-40",
                NULL,
            },
        },
        {
            "removal is case-insensitive",
            {"hOsT", NULL},
            SUCCEED,
            {
                "Date",
                "Thr, 25 Jan 2018",
                "Host",
                "somehost",
                "Range",
                "bytes=20-40",
                NULL,
            },
            {
                "Date",
                "Thr, 25 Jan 2018",
                "Range",
                "bytes=20-40",
                NULL,
            },
        },
    };
    unsigned    testcases_count = 16;
    unsigned    test_i          = 0;
    hrb_node_t *list            = NULL;

    TESTING("hrb_node_t (test_hrb_node_set)");

    for (test_i = 0; test_i < testcases_count; test_i++) {
        const hrb_node_t *node   = NULL;
        const testcase   *test   = &(cases[test_i]);
        unsigned          mock_i = 0;

        /*********
         * SETUP *
         *********/

        for (mock_i = 0; test->given[mock_i] != NULL; mock_i += 2) {
            const char *name  = test->given[mock_i];
            const char *value = test->given[mock_i + 1];

            FAIL_IF(SUCCEED != H5FD_s3comms_hrb_node_set(&list, name, value))
        }
        /********
         * TEST *
         ********/

        /* perform modification on list
         */
        JSVERIFY(test->returned, H5FD_s3comms_hrb_node_set(&list, test->delta.name, test->delta.value),
                 test->message)

        /* verify resulting list
         */
        node   = list;
        mock_i = 0;
        while (test->expected[mock_i] != NULL && node != NULL) {
            const char *name  = test->expected[mock_i];
            const char *value = test->expected[mock_i + 1];

            JSVERIFY_STR(name, node->name, NULL)
            JSVERIFY_STR(value, node->value, NULL)

            mock_i += 2;
            node = node->next;
        }
        FAIL_IF(test->expected[mock_i] != NULL)
        FAIL_IF(node != NULL)

        /************
         * TEARDOWN *
         ************/

        while (list != NULL) {
            FAIL_IF(SUCCEED != H5FD_s3comms_hrb_node_set(&list, list->name, NULL))
        }
    } /* end for each testcase */

    PASSED();
    return 0;

error:
    while (list != NULL) {
        (void)H5FD_s3comms_hrb_node_set(&list, list->name, NULL);
    }

    return -1;

} /* end test_hrb_node_t() */

/*---------------------------------------------------------------------------
 *
 * Function: test_HMAC_SHA256()
 *
 * Purpose:
 *
 *     Define and verify behavior of `H5FD_s3comms_HMAC_SHA256()`
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_HMAC_SHA256(void)
{

    /*************************
     * test-local structures *
     *************************/

    struct testcase {
        herr_t              ret; /* SUCCEED/FAIL expected from call */
        const unsigned char key[SHA256_DIGEST_LENGTH];
        size_t              key_len;
        const char         *msg;
        size_t              msg_len;
        const char         *exp;       /* not used if ret == FAIL */
        size_t              dest_size; /* if 0, `dest` is not malloc'd */
    };

    /************************
     * test-local variables *
     ************************/

    struct testcase cases[] = {
        {
            SUCCEED,
            {
                0xdb, 0xb8, 0x93, 0xac, 0xc0, 0x10, 0x96, 0x49, 0x18, 0xf1, 0xfd,
                0x43, 0x3a, 0xdd, 0x87, 0xc7, 0x0e, 0x8b, 0x0d, 0xb6, 0xbe, 0x30,
                0xc1, 0xfb, 0xea, 0xfe, 0xfa, 0x5e, 0xc6, 0xba, 0x83, 0x78,
            },
            SHA256_DIGEST_LENGTH,
            "AWS4-HMAC-SHA256\n20130524T000000Z\n20130524/us-east-1/s3/"
            "aws4_request\n7344ae5b7ee6c3e7e6b0fe0640412a37625d1fbfff95c48bbb2dc43964946972",
            strlen("AWS4-HMAC-SHA256\n20130524T000000Z\n20130524/us-east-1/s3/"
                   "aws4_request\n7344ae5b7ee6c3e7e6b0fe0640412a37625d1fbfff95c48bbb2dc43964946972"),
            "f0e8bdb87c964420e857bd35b5d6ed310bd44f0170aba48dd91039c6036bdb41",
            SHA256_DIGEST_LENGTH * 2 + 1, /* +1 for null terminator */
        },
        {
            SUCCEED,
            {'J', 'e', 'f', 'e'},
            4,
            "what do ya want for nothing?",
            28,
            "5bdcc146bf60754e6a042426089575c75a003f089d2739839dec58b964ec3843",
            SHA256_DIGEST_LENGTH * 2 + 1,
        },
        {
            FAIL, "DOESN'T MATTER", 14, "ALSO IRRELEVANT", 15, NULL,
            0, /* dest -> null, resulting in immediate error */
        },
    };
    char *dest    = NULL;
    int   i       = 0;
    int   n_cases = 3;

    TESTING("HMAC_SHA256");

    for (i = 0; i < n_cases; i++) {
        if (cases[i].dest_size == 0) {
            dest = NULL;
        }
        else {
            dest = (char *)malloc(sizeof(char) * cases[i].dest_size);
            assert(dest != NULL);
        }

        JSVERIFY(
            cases[i].ret,
            H5FD_s3comms_HMAC_SHA256(cases[i].key, cases[i].key_len, cases[i].msg, cases[i].msg_len, dest),
            cases[i].msg);
        if (cases[i].ret == SUCCEED) {
#ifdef VERBOSE
            if (0 != strncmp(cases[i].exp, dest, strlen(cases[i].exp))) {
                /* print out how wrong things are, and then fail
                 */
                dest = (char *)realloc(dest, cases[i].dest_size + 1);
                assert(dest != NULL);
                dest[cases[i].dest_size] = 0;
                fprintf(stdout, "ERROR:\n!!! \"%s\"\n != \"%s\"\n", cases[i].exp, dest);
                TEST_ERROR;
            }
#else  /* VERBOSE not defined */
            /* simple pass/fail test
             */
            JSVERIFY(0, strncmp(cases[i].exp, dest, strlen(cases[i].exp)), NULL);
#endif /* VERBOSE */
        }
        free(dest);
    }

    PASSED();
    return 0;

error:
    free(dest);
    return -1;

} /* end test_HMAC_SHA256() */

/*----------------------------------------------------------------------------
 *
 * Function: test_nlowercase()
 *
 * Purpose:
 *
 *     Define and verify behavior of `H5FD_s3comms_nlowercase()`
 *
 *----------------------------------------------------------------------------
 */
static herr_t
test_nlowercase(void)
{
    /*************************
     * test-local structures *
     *************************/

    struct testcase {
        const char *in;
        size_t      len;
        const char *exp;
    };

    /************************
     * test-local variables *
     ************************/

    /* any character after in exp on or after exp[len] is undefined.
     * in this test, kept as the null character for simplicity.
     */
    struct testcase cases[] = {
        {
            "HALlEluJAh",
            6,
            "hallel",
        },
        {
            "all\0 lower",
            10,
            "all\0 lower",
        },
        {
            "to meeeeeee",
            0,
            "",
        },
    };
    char *dest    = NULL;
    int   i       = 0;
    int   n_cases = 3;

    TESTING("nlowercase");

    for (i = 0; i < n_cases; i++) {
        dest = (char *)malloc(sizeof(char) * 16);

        JSVERIFY(SUCCEED, H5FD_s3comms_nlowercase(dest, cases[i].in, cases[i].len), cases[i].in)
        if (cases[i].len > 0) {
            JSVERIFY(0, strncmp(dest, cases[i].exp, cases[i].len), NULL)
        }
        free(dest);
    } /* end for each testcase */

    JSVERIFY(FAIL, H5FD_s3comms_nlowercase(NULL, cases[0].in, cases[0].len), "null destination should fail")

    PASSED();
    return 0;

error:
    free(dest);
    return -1;

} /* end test_nlowercase() */

/*---------------------------------------------------------------------------
 *
 * Function: test_parse_url()
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_parse_url(void)
{
    /*********************
     * test-local macros *
     *********************/

    /*************************
     * test-local structures *
     *************************/

    typedef struct {
        const char *scheme;
        const char *host;
        const char *port;
        const char *path;
        const char *query;
    } const_purl_t;

    struct testcase {
        const char *url;
        herr_t      exp_ret; /* expected return;              */
                             /* if FAIL, `expected` is unused */
        const_purl_t expected;
        const char  *msg;
    };

    /************************
     * test-local variables *
     ************************/

    parsed_url_t   *purl    = NULL;
    unsigned int    i       = 0;
    unsigned int    ncases  = 15;
    struct testcase cases[] = {
        {
            NULL,
            FAIL,
            {NULL, NULL, NULL, NULL, NULL},
            "null url",
        },
        {
            "",
            FAIL,
            {NULL, NULL, NULL, NULL, NULL},
            "empty url",
        },
        {
            "ftp://[1000:4000:0002:2010]",
            SUCCEED,
            {
                "ftp",
                "[1000:4000:0002:2010]",
                NULL,
                NULL,
                NULL,
            },
            "IPv6 ftp and empty path (root)",
        },
        {
            "ftp://[1000:4000:0002:2010]:2040",
            SUCCEED,
            {
                "ftp",
                "[1000:4000:0002:2010]",
                "2040",
                NULL,
                NULL,
            },
            "root IPv6 ftp with port",
        },
        {
            "http://some.domain.org:9000/path/to/resource.txt",
            SUCCEED,
            {
                "http",
                "some.domain.org",
                "9000",
                "path/to/resource.txt",
                NULL,
            },
            "without query",
        },
        {
            "https://domain.me:00/file.txt?some_params unchecked",
            SUCCEED,
            {
                "https",
                "domain.me",
                "00",
                "file.txt",
                "some_params unchecked",
            },
            "with query",
        },
        {
            "ftp://domain.com/",
            SUCCEED,
            {
                "ftp",
                "domain.com",
                NULL,
                NULL,
                NULL,
            },
            "explicit root w/out port",
        },
        {
            "ftp://domain.com:1234/",
            SUCCEED,
            {
                "ftp",
                "domain.com",
                "1234",
                NULL,
                NULL,
            },
            "explicit root with port",
        },
        {
            "ftp://domain.com:1234/file?",
            FAIL,
            {
                NULL,
                NULL,
                NULL,
                NULL,
                NULL,
            },
            "empty query is invalid",
        },
        {
            "ftp://:1234/file",
            FAIL,
            {
                NULL,
                NULL,
                NULL,
                NULL,
                NULL,
            },
            "no host",
        },
        {
            "h&r block",
            FAIL,
            {
                NULL,
                NULL,
                NULL,
                NULL,
                NULL,
            },
            "no scheme (bad URL)",
        },
        {
            "http://domain.com?a=b&d=b",
            SUCCEED,
            {
                "http",
                "domain.com",
                NULL,
                NULL,
                "a=b&d=b",
            },
            "QUERY with implicit PATH",
        },
        {
            "http://[5]/path?a=b&d=b",
            SUCCEED,
            {
                "http",
                "[5]",
                NULL,
                "path",
                "a=b&d=b",
            },
            "IPv6 extraction is really dumb",
        },
        {
            "http://[1234:5678:0910:1112]:port/path",
            FAIL,
            {
                NULL,
                NULL,
                NULL,
                NULL,
                NULL,
            },
            "non-decimal PORT (port)",
        },
        {
            "http://mydomain.com:01a3/path",
            FAIL,
            {
                NULL,
                NULL,
                NULL,
                NULL,
                NULL,
            },
            "non-decimal PORT (01a3)",
        },
    };

    TESTING("url-parsing functionality");

    /*********
     * TESTS *
     *********/

    for (i = 0; i < ncases; i++) {
        assert(purl == NULL);

        JSVERIFY(cases[i].exp_ret, H5FD_s3comms_parse_url(cases[i].url, &purl), cases[i].msg)

        if (cases[i].exp_ret == FAIL) {
            /* on FAIL, `purl` should be untouched--remains NULL */
            FAIL_UNLESS(purl == NULL)
        }
        else {
            /* on SUCCEED, `purl` should be set */
            FAIL_IF(purl == NULL)

            if (cases[i].expected.scheme != NULL) {
                FAIL_IF(NULL == purl->scheme)
                JSVERIFY_STR(cases[i].expected.scheme, purl->scheme, cases[i].msg)
            }
            else {
                FAIL_UNLESS(NULL == purl->scheme)
            }

            if (cases[i].expected.host != NULL) {
                FAIL_IF(NULL == purl->host)
                JSVERIFY_STR(cases[i].expected.host, purl->host, cases[i].msg)
            }
            else {
                FAIL_UNLESS(NULL == purl->host)
            }

            if (cases[i].expected.port != NULL) {
                FAIL_IF(NULL == purl->port)
                JSVERIFY_STR(cases[i].expected.port, purl->port, cases[i].msg)
            }
            else {
                FAIL_UNLESS(NULL == purl->port)
            }

            if (cases[i].expected.path != NULL) {
                FAIL_IF(NULL == purl->path)
                JSVERIFY_STR(cases[i].expected.path, purl->path, cases[i].msg)
            }
            else {
                FAIL_UNLESS(NULL == purl->path)
            }

            if (cases[i].expected.query != NULL) {
                FAIL_IF(NULL == purl->query)
                JSVERIFY_STR(cases[i].expected.query, purl->query, cases[i].msg)
            }
            else {
                FAIL_UNLESS(NULL == purl->query)
            }
        } /* end if parse-url return SUCCEED/FAIL */

        /* per-test cleanup
         * well-behaved, even if `purl` is NULL
         */
        FAIL_IF(FAIL == H5FD_s3comms_free_purl(purl))
        purl = NULL;

    } /* end for each testcase */

    PASSED();
    return 0;

error:
    /***********
     * cleanup *
     ***********/
    (void)H5FD_s3comms_free_purl(purl);

    return -1;

} /* end test_parse_url() */

/*---------------------------------------------------------------------------
 *
 * Function: test_percent_encode_char()
 *
 * Purpose:
 *
 *     Define and verify behavior of `H5FD_s3comms_percent_encode_char()`
 *
 * Return:
 *
 *     Success:  0
 *     Failure: -1
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_percent_encode_char(void)
{
    /*************************
     * test-local structures *
     *************************/

    struct testcase {
        const char  c;
        const char *exp;
        size_t      exp_len;
    };

    /************************
     * test-local variables *
     ************************/

    struct testcase cases[] = {
        {'$', "%24", 3},        /* u+0024 dollar sign */
        {' ', "%20", 3},        /* u+0020 space */
        {'^', "%5E", 3},        /* u+0094 carat */
        {'/', "%2F", 3},        /* u+002f solidus (forward slash) */
        /* {??, "%C5%8C", 6},*/ /* u+014c Latin Capital Letter O with Macron */
        /* Not included because it is multibyte "wide" character that poses  */
        /* issues both in the underlying function and in being written in    */
        /* this file.                                                        */
        /* {'¢', "%C2%A2", 6}, */ /* u+00a2 cent sign */
        /* above works, but complains about wide character overflow      */
        /* Elide for now, until it is determined (a) unnecessary or      */
        /* (b) requiring signature change to accommodate wide characters */
        {'\0', "%00", 3}, /* u+0000 null */
    };
    char   dest[13];
    size_t dest_len = 0;
    int    i        = 0;
    int    n_cases  = 5;

    TESTING("percent encode characters");

    for (i = 0; i < n_cases; i++) {
        JSVERIFY(SUCCEED, H5FD_s3comms_percent_encode_char(dest, (const unsigned char)cases[i].c, &dest_len),
                 NULL)
        JSVERIFY(cases[i].exp_len, dest_len, NULL)
        JSVERIFY(0, strncmp(dest, cases[i].exp, dest_len), NULL)
        JSVERIFY_STR(cases[i].exp, dest, NULL)
    }

    JSVERIFY(FAIL, H5FD_s3comms_percent_encode_char(NULL, (const unsigned char)'^', &dest_len), NULL)

    PASSED();
    return 0;

error:
    return -1;
} /* end test_percent_encode_char() */

/*---------------------------------------------------------------------------
 * Function: test_s3r_get_filesize()
 *---------------------------------------------------------------------------
 */
static herr_t
test_s3r_get_filesize(void)
{

    /************************
     * test-local variables *
     ************************/

    char   url_raven[S3_TEST_MAX_URL_SIZE];
    s3r_t *handle = NULL;

    TESTING("s3r_get_filesize");

    /* setup -- compose url to target resource
     */
    if (false == s3_test_bucket_defined) {
        SKIPPED();
        puts("    environment variable HDF5_ROS3_TEST_BUCKET_URL not defined");
        fflush(stdout);
        return 0;
    }

    FAIL_IF(S3_TEST_MAX_URL_SIZE < snprintf(url_raven, S3_TEST_MAX_URL_SIZE, "%s/%s", s3_test_bucket_url,
                                            S3_TEST_RESOURCE_TEXT_PUBLIC));

    JSVERIFY(0, H5FD_s3comms_s3r_get_filesize(NULL), "filesize of the null handle should be 0")

    handle = H5FD_s3comms_s3r_open(url_raven, NULL, NULL, NULL, NULL);
    FAIL_IF(handle == NULL)

    JSVERIFY(6464, H5FD_s3comms_s3r_get_filesize(handle), NULL)

    FAIL_IF(SUCCEED != H5FD_s3comms_s3r_close(handle))

    PASSED();
    return 0;

error:
    if (handle != NULL)
        (void)H5FD_s3comms_s3r_close(handle);

    return -1;

} /* end test_s3r_get_filesize() */

/*---------------------------------------------------------------------------
 * Function: test_s3r_open()
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_s3r_open(void)
{

    /************************
     * test-local variables *
     ************************/

    char          url_missing[S3_TEST_MAX_URL_SIZE];
    char          url_raven[S3_TEST_MAX_URL_SIZE];
    char          url_raven_badport[S3_TEST_MAX_URL_SIZE];
    char          url_shakespeare[S3_TEST_MAX_URL_SIZE];
    unsigned char signing_key[SHA256_DIGEST_LENGTH];
    struct tm    *now = NULL;
    char          iso8601now[ISO8601_SIZE];
    s3r_t        *handle     = NULL;
    bool          curl_ready = false;
    parsed_url_t *purl       = NULL;

    TESTING("s3r_open");

    if (s3_test_credentials_loaded == 0) {
        SKIPPED();
        puts("    s3 credentials are not loaded");
        fflush(stdout);
        return 0;
    }
    if (false == s3_test_bucket_defined) {
        SKIPPED();
        puts("    environment variable HDF5_ROS3_TEST_BUCKET_URL not defined");
        fflush(stdout);
        return 0;
    }

    /******************
     * PRE-TEST SETUP *
     ******************/

    FAIL_IF(S3_TEST_MAX_URL_SIZE < snprintf(url_shakespeare, S3_TEST_MAX_URL_SIZE, "%s/%s",
                                            s3_test_bucket_url, S3_TEST_RESOURCE_TEXT_RESTRICTED));

    FAIL_IF(S3_TEST_MAX_URL_SIZE < snprintf(url_missing, S3_TEST_MAX_URL_SIZE, "%s/%s", s3_test_bucket_url,
                                            S3_TEST_RESOURCE_MISSING));

    FAIL_IF(S3_TEST_MAX_URL_SIZE < snprintf(url_raven, S3_TEST_MAX_URL_SIZE, "%s/%s", s3_test_bucket_url,
                                            S3_TEST_RESOURCE_TEXT_PUBLIC));

    /* Set given bucket url with invalid/inactive port number for badport.
     * Note, this sort of micro-management of parsed_url_t is not advised
     */
    FAIL_IF(FAIL == H5FD_s3comms_parse_url(s3_test_bucket_url, &purl))
    if (purl->port == NULL) {
        purl->port = (char *)H5MM_malloc(sizeof(char) * 5);
        FAIL_IF(purl->port == NULL);
        FAIL_IF(5 < snprintf(purl->port, 5, "9000"))
    }
    else if (strcmp(purl->port, "9000") != 0) {
        FAIL_IF(5 < snprintf(purl->port, 5, "9000"))
    }
    else {
        FAIL_IF(5 < snprintf(purl->port, 5, "1234"))
    }
    FAIL_IF(S3_TEST_MAX_URL_SIZE < snprintf(url_raven_badport, S3_TEST_MAX_URL_SIZE, "%s://%s:%s/%s",
                                            purl->scheme, purl->host, purl->port,
                                            S3_TEST_RESOURCE_TEXT_PUBLIC));

    curl_global_init(CURL_GLOBAL_DEFAULT);
    curl_ready = true;

    now = gmnow();
    FAIL_IF(now == NULL)
    FAIL_IF(ISO8601NOW(iso8601now, now) != (ISO8601_SIZE - 1));

    /* It is desired to have means available to verify that signing_key
     * was set successfully and to an expected value.
     */
    FAIL_IF(FAIL == H5FD_s3comms_signing_key(signing_key, (const char *)s3_test_aws_secret_access_key,
                                             (const char *)s3_test_aws_region, (const char *)iso8601now));

    /*************************
     * OPEN NONEXISTENT FILE *
     *************************/

    /* attempt anonymously
     */
    handle = H5FD_s3comms_s3r_open(url_missing, NULL, NULL, NULL, NULL);
    FAIL_IF(handle != NULL);

    /* attempt with authentication
     */
    handle = H5FD_s3comms_s3r_open(
        url_missing, (const char *)s3_test_aws_region, (const char *)s3_test_aws_access_key_id,
        (const unsigned char *)signing_key, (const char *)s3_test_aws_security_token);
    FAIL_IF(handle != NULL);

    /*************************
     * INACTIVE PORT ON HOST *
     *************************/

#if S3_TEST_RUN_TIMEOUT
    printf("Opening on inactive port may hang for a minute; waiting for timeout\n");
    handle = H5FD_s3comms_s3r_open(url_raven_badport, NULL, NULL, NULL, NULL);
    FAIL_IF(handle != NULL);
#endif

    /*******************************
     * INVALID AUTHENTICATION INFO *
     *******************************/

    /* anonymous access on restricted file
     */
    handle = H5FD_s3comms_s3r_open(url_shakespeare, NULL, NULL, NULL, NULL);
    FAIL_IF(handle != NULL);

    /* passed in a bad ID
     */
    handle =
        H5FD_s3comms_s3r_open(url_shakespeare, (const char *)s3_test_aws_region, "I_MADE_UP_MY_ID",
                              (const unsigned char *)signing_key, (const char *)s3_test_aws_security_token);
    FAIL_IF(handle != NULL);

    /* using an invalid signing key
     */
    handle = H5FD_s3comms_s3r_open(
        url_shakespeare, (const char *)s3_test_aws_region, (const char *)s3_test_aws_access_key_id,
        (const unsigned char *)EMPTY_SHA256, (const char *)s3_test_aws_security_token);
    FAIL_IF(handle != NULL);

    /*******************************
     * SUCCESSFUL OPEN (AND CLOSE) *
     *******************************/

    /* anonymous
     */
    handle = H5FD_s3comms_s3r_open(url_raven, NULL, NULL, NULL, NULL);
    FAIL_IF(handle == NULL);
    JSVERIFY(6464, H5FD_s3comms_s3r_get_filesize(handle), "did not get expected filesize")
    JSVERIFY(SUCCEED, H5FD_s3comms_s3r_close(handle), "unable to close file")
    handle = NULL;

    /* using authentication on anonymously-accessible file?
     */
    handle = H5FD_s3comms_s3r_open(
        url_raven, (const char *)s3_test_aws_region, (const char *)s3_test_aws_access_key_id,
        (const unsigned char *)signing_key, (const char *)s3_test_aws_security_token);
    FAIL_IF(handle == NULL);
    JSVERIFY(6464, H5FD_s3comms_s3r_get_filesize(handle), NULL)
    JSVERIFY(SUCCEED, H5FD_s3comms_s3r_close(handle), "unable to close file")
    handle = NULL;

    /* authenticating
     */
    handle = H5FD_s3comms_s3r_open(
        url_shakespeare, (const char *)s3_test_aws_region, (const char *)s3_test_aws_access_key_id,
        (const unsigned char *)signing_key, (const char *)s3_test_aws_security_token);
    FAIL_IF(handle == NULL);
    JSVERIFY(5458199, H5FD_s3comms_s3r_get_filesize(handle), NULL)
    JSVERIFY(SUCCEED, H5FD_s3comms_s3r_close(handle), "unable to close file")
    handle = NULL;

    curl_global_cleanup();
    curl_ready = false;

    FAIL_IF(FAIL == H5FD_s3comms_free_purl(purl))
    purl = NULL;

    PASSED();
    return 0;
error:
    /***********
     * cleanup *
     ***********/

    if (handle != NULL)
        H5FD_s3comms_s3r_close(handle);
    if (purl != NULL)
        H5FD_s3comms_free_purl(purl);
    if (curl_ready == true)
        curl_global_cleanup();

    return -1;

} /* end test_s3r_open() */

/*---------------------------------------------------------------------------
 *
 * Function: test_s3r_read()
 *
 * Purpose:
 *
 *     Specify and demonstrate the use and life cycle of an S3 Request handle
 *     `s3r_t`, through its related functions.
 *
 *     H5FD_s3comms_s3r_open
 *     H5FD_s3comms_s3r_getsize << called by open() _only_
 *     H5FD_s3comms_s3r_read    << called by getsize(), multiple times working
 *     H5FD_s3comms_s3r_close
 *
 *     Shows most basic curl iteration.
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_s3r_read(void)
{

#define S3COMMS_TEST_BUFFER_SIZE 256

    /************************
     * test-local variables *
     ************************/

    char         url_raven[S3_TEST_MAX_URL_SIZE];
    char         buffer[S3COMMS_TEST_BUFFER_SIZE];
    s3r_t       *handle     = NULL;
    bool         curl_ready = false;
    unsigned int i          = 0;

    TESTING("test_s3r_read");

    /*
     * initial setup
     */
    if (false == s3_test_bucket_defined) {
        SKIPPED();
        puts("    environment variable HDF5_ROS3_TEST_BUCKET_URL not defined");
        fflush(stdout);
        return 0;
    }

    curl_global_init(CURL_GLOBAL_DEFAULT);
    curl_ready = true;
    FAIL_IF(S3_TEST_MAX_URL_SIZE < snprintf(url_raven, S3_TEST_MAX_URL_SIZE, "%s/%s", s3_test_bucket_url,
                                            S3_TEST_RESOURCE_TEXT_PUBLIC));

    for (i = 0; i < S3COMMS_TEST_BUFFER_SIZE; i++)
        buffer[i] = '\0';

    /* open file
     */
    handle = H5FD_s3comms_s3r_open(url_raven, NULL, NULL, NULL, NULL);
    FAIL_IF(handle == NULL)
    JSVERIFY(6464, H5FD_s3comms_s3r_get_filesize(handle), NULL)

    for (i = 0; i < S3COMMS_TEST_BUFFER_SIZE; i++)
        buffer[i] = '\0';

    /**********************
     * read start of file *
     **********************/

    JSVERIFY(SUCCEED, H5FD_s3comms_s3r_read(handle, (haddr_t)0, (size_t)118, buffer), NULL)
    JSVERIFY_STR("Once upon a midnight dreary, while I pondered, weak and weary,\n"
                 "Over many a quaint and curious volume of forgotten lore",
                 buffer, NULL)

    for (i = 0; i < S3COMMS_TEST_BUFFER_SIZE; i++)
        buffer[i] = '\0';

    /************************
     * read arbitrary range *
     ************************/

    JSVERIFY(SUCCEED, H5FD_s3comms_s3r_read(handle, (haddr_t)2540, (size_t)54, buffer), NULL)
    JSVERIFY_STR("the grave and stern decorum of the countenance it wore", buffer, NULL)

    for (i = 0; i < S3COMMS_TEST_BUFFER_SIZE; i++)
        buffer[i] = '\0';

    /**********************
     * read one character *
     **********************/

    JSVERIFY(SUCCEED, H5FD_s3comms_s3r_read(handle, (haddr_t)2540, (size_t)1, buffer), NULL)
    JSVERIFY_STR("t", buffer, NULL)

    for (i = 0; i < S3COMMS_TEST_BUFFER_SIZE; i++)
        buffer[i] = '\0';

    /***************
     * read to EoF *
     ***************/

    JSVERIFY(SUCCEED, H5FD_s3comms_s3r_read(handle, (haddr_t)6370, (size_t)0, buffer), NULL)
    JSVERIFY(
        0,
        strncmp(
            buffer,
            "And my soul from out that shadow that lies floating on the floor\nShall be lifted—nevermore!\n",
            94),
        buffer)

    for (i = 0; i < S3COMMS_TEST_BUFFER_SIZE; i++)
        buffer[i] = '\0';

    /*****************
     * read past eof *
     *****************/

    JSVERIFY(FAIL,
             H5FD_s3comms_s3r_read(handle, (haddr_t)6400, (size_t)100, /* 6400+100 > 6464 */
                                   buffer),
             NULL)
    JSVERIFY(0, strcmp("", buffer), NULL)

    /************************
     * read starts past eof *
     ************************/

    JSVERIFY(FAIL,
             H5FD_s3comms_s3r_read(handle, (haddr_t)1200699, /* 1200699 > 6464 */
                                   (size_t)100, buffer),
             NULL)
    JSVERIFY(0, strcmp("", buffer), NULL)

    /**********************
     * read starts on eof *
     **********************/

    JSVERIFY(FAIL, H5FD_s3comms_s3r_read(handle, (haddr_t)6464, (size_t)0, buffer), NULL)
    JSVERIFY(0, strcmp("", buffer), NULL)

    /*************
     * TEAR DOWN *
     *************/

    JSVERIFY(SUCCEED, H5FD_s3comms_s3r_close(handle), "unable to close file")
    handle = NULL;

    curl_global_cleanup();
    curl_ready = false;

    PASSED();
    return 0;

error:
    /***********
     * cleanup *
     ***********/

    if (handle != NULL)
        H5FD_s3comms_s3r_close(handle);

    if (curl_ready == true)
        curl_global_cleanup();

    return -1;

#undef S3COMMS_TEST_BUFFER_SIZE

} /* end test_s3r_read() */

/*---------------------------------------------------------------------------
 *
 * Function: test_signing_key()
 *
 * Purpose:
 *
 *     Define and verify behavior of `H5FD_s3comms_signing_key()`
 *
 *     More test cases would be a very good idea.
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_signing_key(void)
{
    /*************************
     * test-local structures *
     *************************/

    struct testcase {
        const char   *region;
        const char   *secret_key;
        const char   *when;
        unsigned char exp[SHA256_DIGEST_LENGTH];
    };

    /************************
     * test-local variables *
     ************************/

    struct testcase cases[] = {
        {
            "us-east-1",
            "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY",
            "20130524T000000Z",
            {
                0xdb, 0xb8, 0x93, 0xac, 0xc0, 0x10, 0x96, 0x49, 0x18, 0xf1, 0xfd,
                0x43, 0x3a, 0xdd, 0x87, 0xc7, 0x0e, 0x8b, 0x0d, 0xb6, 0xbe, 0x30,
                0xc1, 0xfb, 0xea, 0xfe, 0xfa, 0x5e, 0xc6, 0xba, 0x83, 0x78,
            },
        },
    };
    int            i      = 0;
    unsigned char *key    = NULL;
    int            ncases = 1;

    TESTING("signing_key");

    for (i = 0; i < ncases; i++) {
        key = (unsigned char *)malloc(sizeof(unsigned char) * SHA256_DIGEST_LENGTH);
        assert(key != NULL);

        JSVERIFY(SUCCEED, H5FD_s3comms_signing_key(key, cases[i].secret_key, cases[i].region, cases[i].when),
                 NULL)

        JSVERIFY(0, strncmp((const char *)cases[i].exp, (const char *)key, SHA256_DIGEST_LENGTH),
                 (const char *)cases[i].exp)

        free(key);
        key = NULL;
    }

    /***************
     * ERROR CASES *
     ***************/

    key = (unsigned char *)malloc(sizeof(unsigned char) * SHA256_DIGEST_LENGTH);
    assert(key != NULL);

    JSVERIFY(FAIL, H5FD_s3comms_signing_key(NULL, cases[0].secret_key, cases[0].region, cases[0].when),
             "destination cannot be NULL")

    JSVERIFY(FAIL, H5FD_s3comms_signing_key(key, NULL, cases[0].region, cases[0].when),
             "secret key cannot be NULL")

    JSVERIFY(FAIL, H5FD_s3comms_signing_key(key, cases[0].secret_key, NULL, cases[0].when),
             "aws region cannot be NULL")

    JSVERIFY(FAIL, H5FD_s3comms_signing_key(key, cases[0].secret_key, cases[0].region, NULL),
             "time string cannot be NULL")

    free(key);
    key = NULL;

    PASSED();
    return 0;

error:
    if (key != NULL) {
        free(key);
    }

    return -1;

} /* end test_signing_key() */

/*---------------------------------------------------------------------------
 *
 * Function: test_tostringtosign()
 *
 * Purpose:
 *
 *     Verify that we can get the "string to sign" from a Canonical Request and
 *     related information.
 *
 *     Demonstrate failure cases.
 *
 * Return:
 *
 *     Success:  0
 *     Failure: -1
 *
 *---------------------------------------------------------------------------
 */
static herr_t
test_tostringtosign(void)
{
    /************************
     * test-local variables *
     ************************/

    const char canonreq[]   = "GET\n/"
                              "test.txt\n\nhost:examplebucket.s3.amazonaws.com\nrange:bytes=0-9\nx-amz-content-"
                              "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855\nx-amz-"
                              "date:20130524T000000Z\n\nhost;range;x-amz-content-sha256;x-amz-"
                              "date\ne3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855";
    const char iso8601now[] = "20130524T000000Z";
    const char region[]     = "us-east-1";
    char       s2s[512];

    TESTING("s3comms tostringtosign");

    JSVERIFY(SUCCEED, H5FD_s3comms_tostringtosign(s2s, canonreq, iso8601now, region),
             "unable to create string to sign")

    JSVERIFY_STR("AWS4-HMAC-SHA256\n20130524T000000Z\n20130524/us-east-1/s3/"
                 "aws4_request\n7344ae5b7ee6c3e7e6b0fe0640412a37625d1fbfff95c48bbb2dc43964946972",
                 s2s, NULL)

    JSVERIFY(FAIL, H5FD_s3comms_tostringtosign(s2s, NULL, iso8601now, region),
             "canonical request string cannot be NULL")

    JSVERIFY(FAIL, H5FD_s3comms_tostringtosign(s2s, canonreq, NULL, region), "time string cannot be NULL")

    JSVERIFY(FAIL, H5FD_s3comms_tostringtosign(s2s, canonreq, iso8601now, NULL), "aws region cannot be NULL")

    PASSED();
    return 0;

error:
    return -1;

} /* end test_tostringtosign() */

/*----------------------------------------------------------------------------
 *
 * Function: test_trim()
 *
 * Purpose:
 *
 *     Define and verify behavior of `H5FD_s3comms_trim()`.
 *
 *----------------------------------------------------------------------------
 */
static herr_t
test_trim(void)
{
    /*************************
     * test-local structures *
     *************************/

    struct testcase {
        const char *in;
        size_t      in_len;
        const char *exp;
        size_t      exp_len;
    };

    /************************
     * test-local variables *
     ************************/

    struct testcase cases[] = {
        {
            "block string",
            12,
            "block string",
            12,
        },
        {
            " \n\r  \t",
            6,
            "",
            0,
        },
        {
            " \twhite b4",
            10,
            "white b4",
            8,
        },
        {
            "white after\r\n  ",
            15,
            "white after",
            11,
        },
        {
            " on\nends\t",
            9,
            "on\nends",
            7,
        },
    };
    char   dest[32];
    size_t dest_len = 0;
    int    i        = 0;
    int    n_cases  = 5;
    char  *str      = NULL;

    TESTING("s3comms trim");

    for (i = 0; i < n_cases; i++) {
        assert(str == NULL);
        str = (char *)malloc(sizeof(char) * cases[i].in_len);
        assert(str != NULL);
        strncpy(str, cases[i].in, cases[i].in_len);

        JSVERIFY(SUCCEED, H5FD_s3comms_trim(dest, str, cases[i].in_len, &dest_len), NULL)
        JSVERIFY(cases[i].exp_len, dest_len, cases[i].in)
        if (dest_len > 0) {
            JSVERIFY(0, strncmp(cases[i].exp, dest, dest_len), cases[i].exp)
        }
        free(str);
        str = NULL;
    } /* end for each testcase */

    JSVERIFY(SUCCEED, H5FD_s3comms_trim(dest, NULL, 3, &dest_len),
             "should not fail when trimming a null string");
    JSVERIFY(0, dest_len, "trimming NULL string writes 0 characters")

    assert(str == NULL);
    str = (char *)malloc(sizeof(char *) * 11);
    assert(str != NULL);
    memcpy(str, "some text ", 11); /* string with null terminator */
    JSVERIFY(FAIL, H5FD_s3comms_trim(NULL, str, 10, &dest_len), "destination for trim cannot be NULL");
    free(str);
    str = NULL;

    PASSED();
    return 0;

error:
    if (str != NULL) {
        free(str);
    }
    return -1;

} /* end test_trim() */

/*----------------------------------------------------------------------------
 *
 * Function: test_uriencode()
 *
 * Purpose:
 *
 *     Define and verify behavior of `H5FD_s3comms_uriencode()`.
 *
 *----------------------------------------------------------------------------
 */
static herr_t
test_uriencode(void)
{
    /*************************
     * test-local structures *
     *************************/

    struct testcase {
        const char *str;
        size_t      s_len;
        bool        encode_slash;
        const char *expected;
    };

    /************************
     * test-local variables *
     ************************/

    struct testcase cases[]      = {{
                                   "/path/to/resource.jpg",
                                   21,
                                   false,
                                   "/path/to/resource.jpg",
                               },
                               {
                                   "/path/to/resource.jpg",
                                   21,
                                   true,
                                   "%2Fpath%2Fto%2Fresource.jpg",
                               },
                               {
                                   "string got_spaa  ces",
                                   20,
                                   true,
                                   "string%20got_spaa%20%20ces",
                               },
                               {
                                   "sp ac~es/and-sl ash.encoded",
                                   27,
                                   true,
                                   "sp%20ac~es%2Fand-sl%20ash.encoded",
                               },
                               {
                                   "sp ac~es/and-sl ash.unencoded",
                                   29,
                                   false,
                                   "sp%20ac~es/and-sl%20ash.unencoded",
                               },
                               {
                                   "/path/to/resource.txt",
                                   0,
                                   false,
                                   "",

                               }};
    char           *dest         = NULL;
    size_t          dest_written = 0;
    int             i            = 0;
    int             ncases       = 6;
    size_t          str_len      = 0;

    TESTING("s3comms uriencode");

    for (i = 0; i < ncases; i++) {
        str_len = cases[i].s_len;
        dest    = (char *)malloc(sizeof(char) * str_len * 3 + 1);
        FAIL_IF(dest == NULL)

        JSVERIFY(SUCCEED,
                 H5FD_s3comms_uriencode(dest, cases[i].str, str_len, cases[i].encode_slash, &dest_written),
                 NULL);
        JSVERIFY(strlen(cases[i].expected), dest_written, NULL)
        JSVERIFY(0, strncmp(dest, cases[i].expected, dest_written), cases[i].expected);

        free(dest);
        dest = NULL;
    } /* end for each testcase */

    /***************
     * ERROR CASES *
     ***************/

    dest = (char *)malloc(sizeof(char) * 15);
    assert(dest != NULL);

    JSVERIFY(FAIL, H5FD_s3comms_uriencode(NULL, "word$", 5, false, &dest_written),
             "destination cannot be NULL");
    JSVERIFY(FAIL, H5FD_s3comms_uriencode(dest, NULL, 5, false, &dest_written),
             "source string cannot be NULL");

    free(dest);
    dest = NULL;

    PASSED();
    return 0;

error:
    if (dest != NULL) {
        free(dest);
    }
    return -1;

} /* end test_uriencode() */

#endif /* H5_HAVE_ROS3_VFD */

/*-------------------------------------------------------------------------
 * Function: main()
 *
 * Purpose:
 *
 *     Run unit tests for S3 Communications (s3comms).
 *
 * Return:
 *
 *     Success: 0
 *     Failure: 1
 *
 *-------------------------------------------------------------------------
 */
int
main(void)
{
#ifdef H5_HAVE_ROS3_VFD
    int         nerrors        = 0;
    const char *bucket_url_env = NULL;

    h5_reset();

#endif /* H5_HAVE_ROS3_VFD */

    printf("Testing S3Communications functionality.\n");

#ifdef H5_HAVE_ROS3_VFD

    /* "clear" profile data strings */
    s3_test_aws_access_key_id[0]     = '\0';
    s3_test_aws_secret_access_key[0] = '\0';
    s3_test_aws_region[0]            = '\0';
    s3_test_bucket_url[0]            = '\0';

    /* TODO: unit/regression test for H5FD_s3comms_load_aws_profile()
     * requires a few test files and/or manipulation of default path
     */
    /* attempt to load test credentials
     * if unable, certain tests will be skipped
     */
    if (SUCCEED == H5FD_s3comms_load_aws_profile(S3_TEST_PROFILE_NAME, s3_test_aws_access_key_id,
                                                 s3_test_aws_secret_access_key, s3_test_aws_region)) {
        s3_test_credentials_loaded = 1;
    }

    bucket_url_env = getenv("HDF5_ROS3_TEST_BUCKET_URL");
    if (bucket_url_env == NULL || bucket_url_env[0] == '\0') {
        printf("WARNING: S3 bucket url is not defined in environment "
               "variable 'HDF5_ROS3_TEST_BUCKET_URL'!\n");
    }
    else {
        strncpy(s3_test_bucket_url, bucket_url_env, S3_TEST_MAX_URL_SIZE);
        s3_test_bucket_defined = true;
    }

    /* tests ordered roughly by dependence */
    nerrors += test_macro_format_credential() < 0 ? 1 : 0;
    nerrors += test_trim() < 0 ? 1 : 0;
    nerrors += test_nlowercase() < 0 ? 1 : 0;
    nerrors += test_uriencode() < 0 ? 1 : 0;
    nerrors += test_percent_encode_char() < 0 ? 1 : 0;
    nerrors += test_bytes_to_hex() < 0 ? 1 : 0;
    nerrors += test_HMAC_SHA256() < 0 ? 1 : 0;
    nerrors += test_signing_key() < 0 ? 1 : 0;
    nerrors += test_hrb_node_set() < 0 ? 1 : 0;
    nerrors += test_hrb_init_request() < 0 ? 1 : 0;
    nerrors += test_parse_url() < 0 ? 1 : 0;
    nerrors += test_aws_canonical_request() < 0 ? 1 : 0;
    nerrors += test_tostringtosign() < 0 ? 1 : 0;
    nerrors += test_s3r_open() < 0 ? 1 : 0;
    nerrors += test_s3r_get_filesize() < 0 ? 1 : 0;
    nerrors += test_s3r_read() < 0 ? 1 : 0;

    if (nerrors) {
        printf("***** %d S3comms TEST%s FAILED! *****\n", nerrors, nerrors > 1 ? "S" : "");
        return 1;
    }

    printf("All S3comms tests passed.\n");

    return 0;

#else

    printf("SKIPPED - read-only S3 VFD not built\n");
    return EXIT_SUCCESS;

#endif /* H5_HAVE_ROS3_VFD */

} /* end main() */
