[d53af3c8] | 1 | /*
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| 2 | * Copyright (c) 2015 Jiri Svoboda
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| 3 | * All rights reserved.
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| 4 | *
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| 5 | * Redistribution and use in source and binary forms, with or without
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| 6 | * modification, are permitted provided that the following conditions
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| 7 | * are met:
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| 8 | *
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| 9 | * - Redistributions of source code must retain the above copyright
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| 10 | * notice, this list of conditions and the following disclaimer.
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| 11 | * - Redistributions in binary form must reproduce the above copyright
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| 12 | * notice, this list of conditions and the following disclaimer in the
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| 13 | * documentation and/or other materials provided with the distribution.
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| 14 | * - The name of the author may not be used to endorse or promote products
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| 15 | * derived from this software without specific prior written permission.
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| 16 | *
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| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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| 27 | */
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| 28 |
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| 29 | /** @addtogroup libriff
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| 30 | * @{
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| 31 | */
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| 32 | /**
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| 33 | * @file RIFF chunk.
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| 34 | */
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| 35 |
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| 36 | #include <assert.h>
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| 37 | #include <byteorder.h>
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| 38 | #include <errno.h>
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| 39 | #include <macros.h>
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| 40 | #include <riff/chunk.h>
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[aaf962e6] | 41 | #include <stdbool.h>
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[d53af3c8] | 42 | #include <stdlib.h>
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| 43 |
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| 44 | /** Open RIFF file for writing
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| 45 | *
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| 46 | * @param fname File name
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| 47 | * @param rrw Place to store pointer to RIFF writer
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| 48 | *
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| 49 | * @return EOK on success, ENOMEM if out of memory, EIO if failed to open
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| 50 | * file.
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| 51 | */
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[0ee3157] | 52 | errno_t riff_wopen(const char *fname, riffw_t **rrw)
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[d53af3c8] | 53 | {
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| 54 | riffw_t *rw;
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| 55 |
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| 56 | rw = calloc(1, sizeof(riffw_t));
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| 57 | if (rw == NULL)
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| 58 | return ENOMEM;
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| 59 |
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| 60 | rw->f = fopen(fname, "wb");
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| 61 | if (rw->f == NULL) {
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| 62 | free(rw);
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| 63 | return EIO;
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| 64 | }
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| 65 |
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| 66 | *rrw = rw;
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| 67 | return EOK;
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| 68 | }
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| 69 |
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| 70 | /** Close RIFF for writing.
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| 71 | *
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| 72 | * @param rw RIFF writer
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| 73 | * @return EOK on success. On write error EIO is returned and RIFF writer
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| 74 | * is destroyed anyway.
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| 75 | */
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[0ee3157] | 76 | errno_t riff_wclose(riffw_t *rw)
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[d53af3c8] | 77 | {
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| 78 | int rv;
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| 79 |
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| 80 | rv = fclose(rw->f);
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| 81 | free(rw);
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| 82 |
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| 83 | return (rv == 0) ? EOK : EIO;
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| 84 | }
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| 85 |
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| 86 | /** Write uint32_t value into RIFF file
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| 87 | *
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| 88 | * @param rw RIFF writer
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| 89 | * @param v Value
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| 90 | * @return EOK on success, EIO on error.
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| 91 | */
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[0ee3157] | 92 | errno_t riff_write_uint32(riffw_t *rw, uint32_t v)
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[d53af3c8] | 93 | {
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| 94 | uint32_t vle;
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| 95 |
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| 96 | vle = host2uint32_t_le(v);
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| 97 | if (fwrite(&vle, 1, sizeof(vle), rw->f) < sizeof(vle))
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| 98 | return EIO;
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| 99 |
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| 100 | return EOK;
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| 101 | }
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| 102 |
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| 103 | /** Begin writing chunk.
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| 104 | *
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| 105 | * @param rw RIFF writer
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| 106 | * @param ckid Chunk ID
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| 107 | * @param wchunk Pointer to chunk structure to fill in
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| 108 | *
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| 109 | * @return EOK on success, EIO on write error
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| 110 | */
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[0ee3157] | 111 | errno_t riff_wchunk_start(riffw_t *rw, riff_ckid_t ckid, riff_wchunk_t *wchunk)
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[d53af3c8] | 112 | {
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| 113 | long pos;
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[0ee3157] | 114 | errno_t rc;
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[d53af3c8] | 115 |
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| 116 | pos = ftell(rw->f);
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| 117 | if (pos < 0)
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| 118 | return EIO;
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| 119 |
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[003c413] | 120 | wchunk->ckstart = pos + 2 * sizeof(uint32_t);
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[d53af3c8] | 121 |
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| 122 | rc = riff_write_uint32(rw, ckid);
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| 123 | if (rc != EOK) {
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| 124 | assert(rc == EIO);
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| 125 | return EIO;
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| 126 | }
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| 127 |
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| 128 | rc = riff_write_uint32(rw, 0);
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| 129 | if (rc != EOK) {
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| 130 | assert(rc == EIO);
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| 131 | return EIO;
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| 132 | }
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| 133 |
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| 134 | return EOK;
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| 135 | }
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| 136 |
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| 137 | /** Finish writing chunk.
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| 138 | *
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| 139 | * @param rw RIFF writer
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| 140 | * @param wchunk Pointer to chunk structure
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| 141 | *
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| 142 | * @return EOK on success, EIO error.
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| 143 | */
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[0ee3157] | 144 | errno_t riff_wchunk_end(riffw_t *rw, riff_wchunk_t *wchunk)
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[d53af3c8] | 145 | {
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| 146 | long pos;
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| 147 | long cksize;
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[0ee3157] | 148 | errno_t rc;
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[d53af3c8] | 149 |
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| 150 | pos = ftell(rw->f);
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| 151 | if (pos < 0)
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| 152 | return EIO;
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| 153 |
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[003c413] | 154 | cksize = pos - wchunk->ckstart;
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[d145ecb] | 155 | if (pos % 2 != 0)
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| 156 | ++pos;
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[d53af3c8] | 157 |
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[003c413] | 158 | if (fseek(rw->f, wchunk->ckstart - 4, SEEK_SET) < 0)
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[d53af3c8] | 159 | return EIO;
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| 160 |
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| 161 | rc = riff_write_uint32(rw, cksize);
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| 162 | if (rc != EOK) {
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| 163 | assert(rc == EIO);
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| 164 | return EIO;
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| 165 | }
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| 166 |
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| 167 | if (fseek(rw->f, pos, SEEK_SET) < 0)
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| 168 | return EIO;
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| 169 |
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| 170 | return EOK;
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| 171 | }
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| 172 |
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| 173 | /** Write data into RIFF file.
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| 174 | *
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| 175 | * @param rw RIFF writer
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| 176 | * @param data Pointer to data
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| 177 | * @param bytes Number of bytes to write
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| 178 | *
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| 179 | * @return EOK on success, EIO on error.
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| 180 | */
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[d145ecb] | 181 | errno_t riff_write(riffw_t *rw, void *data, size_t bytes)
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[d53af3c8] | 182 | {
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| 183 | size_t nw;
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| 184 |
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| 185 | nw = fwrite(data, 1, bytes, rw->f);
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| 186 | if (nw != bytes)
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| 187 | return EIO;
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| 188 |
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| 189 | return EOK;
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| 190 | }
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| 191 |
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| 192 | /** Open RIFF file for reading.
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| 193 | *
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| 194 | * @param fname File name
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[003c413] | 195 | * @param riffck Place to store root (RIFF) chunk
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[d53af3c8] | 196 | * @param rrr Place to store pointer to RIFF reader
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| 197 | *
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| 198 | * @return EOK on success, ENOMEM if out of memory, EIO if failed to open
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| 199 | * file..
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| 200 | */
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[003c413] | 201 | errno_t riff_ropen(const char *fname, riff_rchunk_t *riffck, riffr_t **rrr)
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[d53af3c8] | 202 | {
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| 203 | riffr_t *rr;
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[003c413] | 204 | riff_rchunk_t fchunk;
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| 205 | long fsize;
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[0ee3157] | 206 | errno_t rc;
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[003c413] | 207 | int rv;
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[d53af3c8] | 208 |
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| 209 | rr = calloc(1, sizeof(riffr_t));
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| 210 | if (rr == NULL) {
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| 211 | rc = ENOMEM;
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| 212 | goto error;
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| 213 | }
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| 214 |
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| 215 | rr->f = fopen(fname, "rb");
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| 216 | if (rr->f == NULL) {
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| 217 | rc = EIO;
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| 218 | goto error;
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| 219 | }
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| 220 |
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[003c413] | 221 | rv = fseek(rr->f, 0, SEEK_END);
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| 222 | if (rv < 0) {
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| 223 | rc = EIO;
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| 224 | goto error;
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| 225 | }
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| 226 |
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| 227 | fsize = ftell(rr->f);
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| 228 | if (fsize < 0) {
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| 229 | rc = EIO;
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| 230 | goto error;
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| 231 | }
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| 232 |
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| 233 | rv = fseek(rr->f, 0, SEEK_SET);
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| 234 | if (rv < 0) {
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| 235 | rc = EIO;
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| 236 | goto error;
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| 237 | }
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| 238 |
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| 239 | fchunk.riffr = rr;
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| 240 | fchunk.ckstart = 0;
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| 241 | fchunk.cksize = fsize;
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| 242 |
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| 243 | rc = riff_rchunk_start(&fchunk, riffck);
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| 244 | if (rc != EOK)
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| 245 | goto error;
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| 246 |
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[d53af3c8] | 247 | *rrr = rr;
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| 248 | return EOK;
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| 249 | error:
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| 250 | if (rr != NULL && rr->f != NULL)
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| 251 | fclose(rr->f);
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| 252 | free(rr);
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| 253 | return rc;
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| 254 | }
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| 255 |
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| 256 | /** Close RIFF for reading.
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| 257 | *
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| 258 | * @param rr RIFF reader
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| 259 | * @return EOK on success, EIO on error.
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| 260 | */
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[0ee3157] | 261 | errno_t riff_rclose(riffr_t *rr)
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[d53af3c8] | 262 | {
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[0ee3157] | 263 | errno_t rc;
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[d53af3c8] | 264 |
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| 265 | rc = fclose(rr->f);
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| 266 | free(rr);
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| 267 | return rc == 0 ? EOK : EIO;
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| 268 | }
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| 269 |
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| 270 | /** Read uint32_t from RIFF file.
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| 271 | *
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[003c413] | 272 | * @param rchunk RIFF chunk
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[d53af3c8] | 273 | * @param v Place to store value
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[aaf962e6] | 274 | * @return EOK on success, ELIMIT if at the end of parent chunk, EIO on error.
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[d53af3c8] | 275 | */
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[003c413] | 276 | errno_t riff_read_uint32(riff_rchunk_t *rchunk, uint32_t *v)
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[d53af3c8] | 277 | {
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| 278 | uint32_t vle;
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[003c413] | 279 | errno_t rc;
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| 280 | size_t nread;
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[d53af3c8] | 281 |
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[003c413] | 282 | rc = riff_read(rchunk, &vle, sizeof(vle), &nread);
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| 283 | if (rc != EOK)
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| 284 | return rc;
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[d53af3c8] | 285 |
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[d145ecb] | 286 | if (nread != sizeof(vle))
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| 287 | return ELIMIT;
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| 288 |
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[d53af3c8] | 289 | *v = uint32_t_le2host(vle);
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| 290 | return EOK;
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| 291 | }
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| 292 |
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| 293 | /** Start reading RIFF chunk.
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| 294 | *
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[003c413] | 295 | * @param parent Parent chunk
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[d53af3c8] | 296 | * @param rchunk Pointer to chunk structure to fill in
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| 297 | *
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[aaf962e6] | 298 | * @return EOK on success, ELIMIT if at the end of parent chunk,
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| 299 | * EIO on error.
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[d53af3c8] | 300 | */
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[003c413] | 301 | errno_t riff_rchunk_start(riff_rchunk_t *parent, riff_rchunk_t *rchunk)
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[d53af3c8] | 302 | {
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[0ee3157] | 303 | errno_t rc;
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[d53af3c8] | 304 | long pos;
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| 305 |
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[003c413] | 306 | pos = ftell(parent->riffr->f);
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[d53af3c8] | 307 | if (pos < 0) {
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| 308 | rc = EIO;
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| 309 | goto error;
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| 310 | }
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| 311 |
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[003c413] | 312 | rchunk->riffr = parent->riffr;
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| 313 | rchunk->ckstart = pos + 8;
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| 314 | rc = riff_read_uint32(parent, &rchunk->ckid);
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[d53af3c8] | 315 | if (rc != EOK)
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| 316 | goto error;
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[003c413] | 317 | rc = riff_read_uint32(parent, &rchunk->cksize);
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[d53af3c8] | 318 | if (rc != EOK)
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| 319 | goto error;
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| 320 |
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| 321 | return EOK;
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| 322 | error:
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| 323 | return rc;
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| 324 | }
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| 325 |
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[aaf962e6] | 326 | /** Find and start reading RIFF chunk of with specific chunk ID.
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| 327 | * Other types of chunks are skipped.
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| 328 | *
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| 329 | * @param parent Parent chunk
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| 330 | * @param rchunk Pointer to chunk structure to fill in
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| 331 | *
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| 332 | * @return EOK on success, ENOENT chunk was not found and end was reached
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| 333 | * EIO on error.
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| 334 | */
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| 335 | errno_t riff_rchunk_match(riff_rchunk_t *parent, riff_ckid_t ckid,
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| 336 | riff_rchunk_t *rchunk)
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| 337 | {
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| 338 | errno_t rc;
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| 339 |
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| 340 | while (true) {
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| 341 | rc = riff_rchunk_start(parent, rchunk);
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| 342 | if (rc == ELIMIT)
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| 343 | return ENOENT;
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| 344 | if (rc != EOK)
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| 345 | return rc;
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| 346 |
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| 347 | if (rchunk->ckid == ckid)
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| 348 | break;
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| 349 |
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| 350 | rc = riff_rchunk_end(rchunk);
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| 351 | if (rc != EOK)
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| 352 | return rc;
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| 353 | }
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| 354 |
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| 355 | return EOK;
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| 356 | }
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| 357 |
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| 358 | /** Find and start reading RIFF LIST chunk of specified type.
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| 359 | * Other chunks or LIST chunks of other type are skipped.
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| 360 | *
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| 361 | * @param parent Parent chunk
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| 362 | * @param rchunk Pointer to chunk structure to fill in
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| 363 | *
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| 364 | * @return EOK on success, ENOENT chunk was not found and end was reached
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| 365 | * EIO on error.
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| 366 | */
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| 367 | errno_t riff_rchunk_list_match(riff_rchunk_t *parent, riff_ltype_t ltype,
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| 368 | riff_rchunk_t *rchunk)
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| 369 | {
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| 370 | errno_t rc;
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| 371 | riff_ltype_t rltype;
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| 372 |
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| 373 | while (true) {
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| 374 | rc = riff_rchunk_match(parent, CKID_LIST, rchunk);
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| 375 | if (rc == ELIMIT)
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| 376 | return ENOENT;
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| 377 | if (rc != EOK)
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| 378 | return rc;
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| 379 |
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| 380 | rc = riff_read_uint32(parent, &rltype);
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| 381 | if (rc != EOK)
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| 382 | return rc;
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| 383 |
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| 384 | if (rltype == ltype)
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| 385 | break;
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| 386 |
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| 387 | rc = riff_rchunk_end(rchunk);
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| 388 | if (rc != EOK)
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| 389 | return rc;
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| 390 | }
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| 391 |
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| 392 | return EOK;
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| 393 | }
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| 394 |
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[ea459d4] | 395 | /** Seek to position in chunk.
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| 396 | *
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| 397 | * @param rchunk RIFF chunk
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| 398 | * @param offset Offset
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| 399 | * @param whence SEEK_SET, SEEK_CUR or SEEK_END
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| 400 | * @return EOK on success or an error code
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| 401 | */
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| 402 | errno_t riff_rchunk_seek(riff_rchunk_t *rchunk, long offset, int whence)
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| 403 | {
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| 404 | long pos;
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| 405 | long dest;
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| 406 | int rv;
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| 407 |
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| 408 | switch (whence) {
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| 409 | case SEEK_SET:
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| 410 | dest = rchunk->ckstart + offset;
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| 411 | break;
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| 412 | case SEEK_END:
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| 413 | dest = rchunk->ckstart + rchunk->cksize + offset;
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| 414 | break;
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| 415 | case SEEK_CUR:
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| 416 | pos = ftell(rchunk->riffr->f);
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| 417 | if (pos < 0)
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| 418 | return EIO;
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| 419 | dest = pos + offset;
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| 420 | break;
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| 421 | default:
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| 422 | return EINVAL;
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| 423 | }
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| 424 |
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[57d923e1] | 425 | if (dest < rchunk->ckstart || (unsigned long) dest >
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| 426 | (unsigned long) rchunk->ckstart + rchunk->cksize) {
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[ea459d4] | 427 | return ELIMIT;
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[efe0881] | 428 | }
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[ea459d4] | 429 |
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| 430 | rv = fseek(rchunk->riffr->f, dest, SEEK_SET);
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| 431 | if (rv < 0)
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| 432 | return EIO;
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| 433 |
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| 434 | return EOK;
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| 435 | }
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| 436 |
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[d145ecb] | 437 | /** Return chunk data size.
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| 438 | *
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| 439 | * @param rchunk RIFF chunk
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| 440 | * @return Pure data size (excluding type+size header) in bytes
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| 441 | */
|
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| 442 | uint32_t riff_rchunk_size(riff_rchunk_t *rchunk)
|
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| 443 | {
|
---|
| 444 | return rchunk->cksize;
|
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| 445 | }
|
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| 446 |
|
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[d53af3c8] | 447 | /** Return file offset where chunk ends
|
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| 448 | *
|
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| 449 | * @param rchunk RIFF chunk
|
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| 450 | * @return File offset just after last data byte of the chunk
|
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| 451 | */
|
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| 452 | static long riff_rchunk_get_end(riff_rchunk_t *rchunk)
|
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| 453 | {
|
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[003c413] | 454 | return rchunk->ckstart + rchunk->cksize;
|
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[d53af3c8] | 455 | }
|
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| 456 |
|
---|
| 457 | /** Return file offset of first (non-padding) byte after end of chunk.
|
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| 458 | *
|
---|
| 459 | * @param rchunk RIFF chunk
|
---|
| 460 | * @return File offset of first non-padding byte after end of chunk
|
---|
| 461 | */
|
---|
| 462 | static long riff_rchunk_get_ndpos(riff_rchunk_t *rchunk)
|
---|
| 463 | {
|
---|
| 464 | long ckend;
|
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| 465 |
|
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| 466 | ckend = riff_rchunk_get_end(rchunk);
|
---|
| 467 | if ((ckend % 2) != 0)
|
---|
| 468 | return ckend + 1;
|
---|
| 469 | else
|
---|
| 470 | return ckend;
|
---|
| 471 | }
|
---|
| 472 |
|
---|
| 473 | /** Finish reading RIFF chunk.
|
---|
| 474 | *
|
---|
[ea459d4] | 475 | * Seek to the first byte after end of chunk. It is allowed, though,
|
---|
| 476 | * to return to the chunk later, e.g. using riff_rchunk_seek(@a rchunk, ..).
|
---|
[d53af3c8] | 477 | *
|
---|
| 478 | * @param rchunk Chunk structure
|
---|
| 479 | * @return EOK on success, EIO on error.
|
---|
| 480 | */
|
---|
[003c413] | 481 | errno_t riff_rchunk_end(riff_rchunk_t *rchunk)
|
---|
[d53af3c8] | 482 | {
|
---|
| 483 | long ckend;
|
---|
| 484 |
|
---|
| 485 | ckend = riff_rchunk_get_ndpos(rchunk);
|
---|
[003c413] | 486 | if (fseek(rchunk->riffr->f, ckend, SEEK_SET) < 0)
|
---|
[d53af3c8] | 487 | return EIO;
|
---|
| 488 |
|
---|
| 489 | return EOK;
|
---|
| 490 | }
|
---|
| 491 |
|
---|
| 492 | /** Read data from RIFF chunk.
|
---|
| 493 | *
|
---|
| 494 | * Attempt to read @a bytes bytes from the chunk. If there is less data
|
---|
| 495 | * left until the end of the chunk, less will be read. The actual number
|
---|
| 496 | * of bytes read is returned in @a *nbytes (can even be 0).
|
---|
| 497 | *
|
---|
[003c413] | 498 | * @param rchunk RIFF chunk for reading
|
---|
[d53af3c8] | 499 | * @param buf Buffer to read to
|
---|
| 500 | * @param bytes Number of bytes to read
|
---|
| 501 | * @param nread Place to store number of bytes actually read
|
---|
| 502 | *
|
---|
| 503 | * @return EOK on success, ELIMIT if file position is not within @a rchunk,
|
---|
| 504 | * EIO on I/O error.
|
---|
| 505 | */
|
---|
[003c413] | 506 | errno_t riff_read(riff_rchunk_t *rchunk, void *buf, size_t bytes,
|
---|
| 507 | size_t *nread)
|
---|
[d53af3c8] | 508 | {
|
---|
| 509 | long pos;
|
---|
| 510 | long ckend;
|
---|
| 511 | long toread;
|
---|
| 512 |
|
---|
[003c413] | 513 | pos = ftell(rchunk->riffr->f);
|
---|
[d53af3c8] | 514 | if (pos < 0)
|
---|
| 515 | return EIO;
|
---|
| 516 |
|
---|
| 517 | ckend = riff_rchunk_get_end(rchunk);
|
---|
| 518 | if (pos < rchunk->ckstart || pos > ckend)
|
---|
| 519 | return ELIMIT;
|
---|
| 520 |
|
---|
| 521 | toread = min(bytes, (size_t)(ckend - pos));
|
---|
| 522 | if (toread == 0) {
|
---|
| 523 | *nread = 0;
|
---|
| 524 | return EOK;
|
---|
| 525 | }
|
---|
| 526 |
|
---|
[003c413] | 527 | *nread = fread(buf, 1, toread, rchunk->riffr->f);
|
---|
[d53af3c8] | 528 | if (*nread == 0)
|
---|
| 529 | return EIO;
|
---|
| 530 |
|
---|
| 531 | return EOK;
|
---|
| 532 | }
|
---|
| 533 |
|
---|
| 534 | /** @}
|
---|
| 535 | */
|
---|