[9] | 1 | /* gzread.c -- zlib functions for reading gzip files |
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| 2 | * Copyright (C) 2004, 2005, 2010 Mark Adler |
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| 3 | * For conditions of distribution and use, see copyright notice in zlib.h |
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| 4 | */ |
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| 5 | |
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| 6 | #include "gzguts.h" |
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| 7 | |
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| 8 | /* Local functions */ |
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| 9 | local int gz_load OF((gz_statep, unsigned char *, unsigned, unsigned *)); |
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| 10 | local int gz_avail OF((gz_statep)); |
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| 11 | local int gz_next4 OF((gz_statep, unsigned long *)); |
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| 12 | local int gz_head OF((gz_statep)); |
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| 13 | local int gz_decomp OF((gz_statep)); |
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| 14 | local int gz_make OF((gz_statep)); |
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| 15 | local int gz_skip OF((gz_statep, z_off64_t)); |
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| 16 | |
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| 17 | /* Use read() to load a buffer -- return -1 on error, otherwise 0. Read from |
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| 18 | state->fd, and update state->eof, state->err, and state->msg as appropriate. |
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| 19 | This function needs to loop on read(), since read() is not guaranteed to |
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| 20 | read the number of bytes requested, depending on the type of descriptor. */ |
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| 21 | local int gz_load(state, buf, len, have) |
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| 22 | gz_statep state; |
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| 23 | unsigned char *buf; |
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| 24 | unsigned len; |
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| 25 | unsigned *have; |
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| 26 | { |
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| 27 | int ret; |
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| 28 | |
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| 29 | *have = 0; |
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| 30 | do { |
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| 31 | ret = read(state->fd, buf + *have, len - *have); |
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| 32 | if (ret <= 0) |
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| 33 | break; |
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| 34 | *have += ret; |
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| 35 | } while (*have < len); |
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| 36 | if (ret < 0) { |
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| 37 | gz_error(state, Z_ERRNO, zstrerror()); |
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| 38 | return -1; |
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| 39 | } |
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| 40 | if (ret == 0) |
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| 41 | state->eof = 1; |
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| 42 | return 0; |
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| 43 | } |
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| 44 | |
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| 45 | /* Load up input buffer and set eof flag if last data loaded -- return -1 on |
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| 46 | error, 0 otherwise. Note that the eof flag is set when the end of the input |
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| 47 | file is reached, even though there may be unused data in the buffer. Once |
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| 48 | that data has been used, no more attempts will be made to read the file. |
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| 49 | gz_avail() assumes that strm->avail_in == 0. */ |
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| 50 | local int gz_avail(state) |
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| 51 | gz_statep state; |
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| 52 | { |
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| 53 | z_streamp strm = &(state->strm); |
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| 54 | |
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| 55 | if (state->err != Z_OK) |
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| 56 | return -1; |
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| 57 | if (state->eof == 0) { |
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| 58 | if (gz_load(state, state->in, state->size, |
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| 59 | (unsigned *)&(strm->avail_in)) == -1) |
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| 60 | return -1; |
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| 61 | strm->next_in = state->in; |
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| 62 | } |
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| 63 | return 0; |
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| 64 | } |
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| 65 | |
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| 66 | /* Get next byte from input, or -1 if end or error. */ |
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| 67 | #define NEXT() ((strm->avail_in == 0 && gz_avail(state) == -1) ? -1 : \ |
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| 68 | (strm->avail_in == 0 ? -1 : \ |
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| 69 | (strm->avail_in--, *(strm->next_in)++))) |
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| 70 | |
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| 71 | /* Get a four-byte little-endian integer and return 0 on success and the value |
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| 72 | in *ret. Otherwise -1 is returned and *ret is not modified. */ |
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| 73 | local int gz_next4(state, ret) |
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| 74 | gz_statep state; |
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| 75 | unsigned long *ret; |
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| 76 | { |
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| 77 | int ch; |
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| 78 | unsigned long val; |
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| 79 | z_streamp strm = &(state->strm); |
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| 80 | |
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| 81 | val = NEXT(); |
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| 82 | val += (unsigned)NEXT() << 8; |
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| 83 | val += (unsigned long)NEXT() << 16; |
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| 84 | ch = NEXT(); |
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| 85 | if (ch == -1) |
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| 86 | return -1; |
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| 87 | val += (unsigned long)ch << 24; |
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| 88 | *ret = val; |
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| 89 | return 0; |
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| 90 | } |
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| 91 | |
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| 92 | /* Look for gzip header, set up for inflate or copy. state->have must be zero. |
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| 93 | If this is the first time in, allocate required memory. state->how will be |
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| 94 | left unchanged if there is no more input data available, will be set to COPY |
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| 95 | if there is no gzip header and direct copying will be performed, or it will |
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| 96 | be set to GZIP for decompression, and the gzip header will be skipped so |
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| 97 | that the next available input data is the raw deflate stream. If direct |
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| 98 | copying, then leftover input data from the input buffer will be copied to |
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| 99 | the output buffer. In that case, all further file reads will be directly to |
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| 100 | either the output buffer or a user buffer. If decompressing, the inflate |
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| 101 | state and the check value will be initialized. gz_head() will return 0 on |
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| 102 | success or -1 on failure. Failures may include read errors or gzip header |
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| 103 | errors. */ |
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| 104 | local int gz_head(state) |
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| 105 | gz_statep state; |
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| 106 | { |
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| 107 | z_streamp strm = &(state->strm); |
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| 108 | int flags; |
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| 109 | unsigned len; |
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| 110 | |
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| 111 | /* allocate read buffers and inflate memory */ |
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| 112 | if (state->size == 0) { |
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| 113 | /* allocate buffers */ |
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| 114 | state->in = malloc(state->want); |
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| 115 | state->out = malloc(state->want << 1); |
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| 116 | if (state->in == NULL || state->out == NULL) { |
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| 117 | if (state->out != NULL) |
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| 118 | free(state->out); |
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| 119 | if (state->in != NULL) |
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| 120 | free(state->in); |
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| 121 | gz_error(state, Z_MEM_ERROR, "out of memory"); |
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| 122 | return -1; |
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| 123 | } |
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| 124 | state->size = state->want; |
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| 125 | |
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| 126 | /* allocate inflate memory */ |
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| 127 | state->strm.zalloc = Z_NULL; |
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| 128 | state->strm.zfree = Z_NULL; |
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| 129 | state->strm.opaque = Z_NULL; |
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| 130 | state->strm.avail_in = 0; |
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| 131 | state->strm.next_in = Z_NULL; |
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| 132 | if (inflateInit2(&(state->strm), -15) != Z_OK) { /* raw inflate */ |
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| 133 | free(state->out); |
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| 134 | free(state->in); |
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| 135 | state->size = 0; |
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| 136 | gz_error(state, Z_MEM_ERROR, "out of memory"); |
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| 137 | return -1; |
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| 138 | } |
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| 139 | } |
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| 140 | |
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| 141 | /* get some data in the input buffer */ |
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| 142 | if (strm->avail_in == 0) { |
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| 143 | if (gz_avail(state) == -1) |
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| 144 | return -1; |
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| 145 | if (strm->avail_in == 0) |
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| 146 | return 0; |
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| 147 | } |
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| 148 | |
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| 149 | /* look for the gzip magic header bytes 31 and 139 */ |
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| 150 | if (strm->next_in[0] == 31) { |
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| 151 | strm->avail_in--; |
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| 152 | strm->next_in++; |
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| 153 | if (strm->avail_in == 0 && gz_avail(state) == -1) |
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| 154 | return -1; |
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| 155 | if (strm->avail_in && strm->next_in[0] == 139) { |
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| 156 | /* we have a gzip header, woo hoo! */ |
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| 157 | strm->avail_in--; |
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| 158 | strm->next_in++; |
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| 159 | |
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| 160 | /* skip rest of header */ |
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| 161 | if (NEXT() != 8) { /* compression method */ |
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| 162 | gz_error(state, Z_DATA_ERROR, "unknown compression method"); |
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| 163 | return -1; |
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| 164 | } |
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| 165 | flags = NEXT(); |
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| 166 | if (flags & 0xe0) { /* reserved flag bits */ |
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| 167 | gz_error(state, Z_DATA_ERROR, "unknown header flags set"); |
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| 168 | return -1; |
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| 169 | } |
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| 170 | NEXT(); /* modification time */ |
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| 171 | NEXT(); |
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| 172 | NEXT(); |
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| 173 | NEXT(); |
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| 174 | NEXT(); /* extra flags */ |
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| 175 | NEXT(); /* operating system */ |
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| 176 | if (flags & 4) { /* extra field */ |
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| 177 | len = (unsigned)NEXT(); |
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| 178 | len += (unsigned)NEXT() << 8; |
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| 179 | while (len--) |
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| 180 | if (NEXT() < 0) |
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| 181 | break; |
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| 182 | } |
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| 183 | if (flags & 8) /* file name */ |
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| 184 | while (NEXT() > 0) |
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| 185 | ; |
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| 186 | if (flags & 16) /* comment */ |
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| 187 | while (NEXT() > 0) |
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| 188 | ; |
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| 189 | if (flags & 2) { /* header crc */ |
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| 190 | NEXT(); |
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| 191 | NEXT(); |
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| 192 | } |
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| 193 | /* an unexpected end of file is not checked for here -- it will be |
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| 194 | noticed on the first request for uncompressed data */ |
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| 195 | |
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| 196 | /* set up for decompression */ |
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| 197 | inflateReset(strm); |
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| 198 | strm->adler = crc32(0L, Z_NULL, 0); |
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| 199 | state->how = GZIP; |
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| 200 | state->direct = 0; |
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| 201 | return 0; |
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| 202 | } |
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| 203 | else { |
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| 204 | /* not a gzip file -- save first byte (31) and fall to raw i/o */ |
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| 205 | state->out[0] = 31; |
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| 206 | state->have = 1; |
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| 207 | } |
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| 208 | } |
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| 209 | |
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| 210 | /* doing raw i/o, save start of raw data for seeking, copy any leftover |
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| 211 | input to output -- this assumes that the output buffer is larger than |
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| 212 | the input buffer, which also assures space for gzungetc() */ |
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| 213 | state->raw = state->pos; |
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| 214 | state->next = state->out; |
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| 215 | if (strm->avail_in) { |
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| 216 | memcpy(state->next + state->have, strm->next_in, strm->avail_in); |
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| 217 | state->have += strm->avail_in; |
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| 218 | strm->avail_in = 0; |
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| 219 | } |
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| 220 | state->how = COPY; |
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| 221 | state->direct = 1; |
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| 222 | return 0; |
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| 223 | } |
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| 224 | |
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| 225 | /* Decompress from input to the provided next_out and avail_out in the state. |
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| 226 | If the end of the compressed data is reached, then verify the gzip trailer |
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| 227 | check value and length (modulo 2^32). state->have and state->next are set |
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| 228 | to point to the just decompressed data, and the crc is updated. If the |
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| 229 | trailer is verified, state->how is reset to LOOK to look for the next gzip |
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| 230 | stream or raw data, once state->have is depleted. Returns 0 on success, -1 |
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| 231 | on failure. Failures may include invalid compressed data or a failed gzip |
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| 232 | trailer verification. */ |
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| 233 | local int gz_decomp(state) |
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| 234 | gz_statep state; |
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| 235 | { |
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| 236 | int ret; |
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| 237 | unsigned had; |
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| 238 | unsigned long crc, len; |
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| 239 | z_streamp strm = &(state->strm); |
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| 240 | |
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| 241 | /* fill output buffer up to end of deflate stream */ |
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| 242 | had = strm->avail_out; |
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| 243 | do { |
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| 244 | /* get more input for inflate() */ |
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| 245 | if (strm->avail_in == 0 && gz_avail(state) == -1) |
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| 246 | return -1; |
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| 247 | if (strm->avail_in == 0) { |
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| 248 | gz_error(state, Z_DATA_ERROR, "unexpected end of file"); |
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| 249 | return -1; |
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| 250 | } |
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| 251 | |
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| 252 | /* decompress and handle errors */ |
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| 253 | ret = inflate(strm, Z_NO_FLUSH); |
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| 254 | if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) { |
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| 255 | gz_error(state, Z_STREAM_ERROR, |
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| 256 | "internal error: inflate stream corrupt"); |
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| 257 | return -1; |
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| 258 | } |
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| 259 | if (ret == Z_MEM_ERROR) { |
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| 260 | gz_error(state, Z_MEM_ERROR, "out of memory"); |
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| 261 | return -1; |
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| 262 | } |
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| 263 | if (ret == Z_DATA_ERROR) { /* deflate stream invalid */ |
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| 264 | gz_error(state, Z_DATA_ERROR, |
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| 265 | strm->msg == NULL ? "compressed data error" : strm->msg); |
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| 266 | return -1; |
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| 267 | } |
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| 268 | } while (strm->avail_out && ret != Z_STREAM_END); |
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| 269 | |
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| 270 | /* update available output and crc check value */ |
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| 271 | state->have = had - strm->avail_out; |
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| 272 | state->next = strm->next_out - state->have; |
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| 273 | strm->adler = crc32(strm->adler, state->next, state->have); |
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| 274 | |
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| 275 | /* check gzip trailer if at end of deflate stream */ |
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| 276 | if (ret == Z_STREAM_END) { |
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| 277 | if (gz_next4(state, &crc) == -1 || gz_next4(state, &len) == -1) { |
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| 278 | gz_error(state, Z_DATA_ERROR, "unexpected end of file"); |
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| 279 | return -1; |
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| 280 | } |
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| 281 | if (crc != strm->adler) { |
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| 282 | gz_error(state, Z_DATA_ERROR, "incorrect data check"); |
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| 283 | return -1; |
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| 284 | } |
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| 285 | if (len != (strm->total_out & 0xffffffffL)) { |
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| 286 | gz_error(state, Z_DATA_ERROR, "incorrect length check"); |
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| 287 | return -1; |
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| 288 | } |
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| 289 | state->how = LOOK; /* ready for next stream, once have is 0 (leave |
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| 290 | state->direct unchanged to remember how) */ |
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| 291 | } |
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| 292 | |
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| 293 | /* good decompression */ |
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| 294 | return 0; |
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| 295 | } |
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| 296 | |
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| 297 | /* Make data and put in the output buffer. Assumes that state->have == 0. |
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| 298 | Data is either copied from the input file or decompressed from the input |
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| 299 | file depending on state->how. If state->how is LOOK, then a gzip header is |
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| 300 | looked for (and skipped if found) to determine wither to copy or decompress. |
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| 301 | Returns -1 on error, otherwise 0. gz_make() will leave state->have as COPY |
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| 302 | or GZIP unless the end of the input file has been reached and all data has |
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| 303 | been processed. */ |
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| 304 | local int gz_make(state) |
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| 305 | gz_statep state; |
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| 306 | { |
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| 307 | z_streamp strm = &(state->strm); |
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| 308 | |
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| 309 | if (state->how == LOOK) { /* look for gzip header */ |
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| 310 | if (gz_head(state) == -1) |
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| 311 | return -1; |
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| 312 | if (state->have) /* got some data from gz_head() */ |
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| 313 | return 0; |
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| 314 | } |
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| 315 | if (state->how == COPY) { /* straight copy */ |
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| 316 | if (gz_load(state, state->out, state->size << 1, &(state->have)) == -1) |
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| 317 | return -1; |
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| 318 | state->next = state->out; |
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| 319 | } |
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| 320 | else if (state->how == GZIP) { /* decompress */ |
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| 321 | strm->avail_out = state->size << 1; |
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| 322 | strm->next_out = state->out; |
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| 323 | if (gz_decomp(state) == -1) |
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| 324 | return -1; |
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| 325 | } |
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| 326 | return 0; |
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| 327 | } |
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| 328 | |
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| 329 | /* Skip len uncompressed bytes of output. Return -1 on error, 0 on success. */ |
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| 330 | local int gz_skip(state, len) |
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| 331 | gz_statep state; |
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| 332 | z_off64_t len; |
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| 333 | { |
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| 334 | unsigned n; |
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| 335 | |
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| 336 | /* skip over len bytes or reach end-of-file, whichever comes first */ |
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| 337 | while (len) |
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| 338 | /* skip over whatever is in output buffer */ |
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| 339 | if (state->have) { |
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| 340 | n = GT_OFF(state->have) || (z_off64_t)state->have > len ? |
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| 341 | (unsigned)len : state->have; |
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| 342 | state->have -= n; |
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| 343 | state->next += n; |
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| 344 | state->pos += n; |
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| 345 | len -= n; |
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| 346 | } |
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| 347 | |
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| 348 | /* output buffer empty -- return if we're at the end of the input */ |
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| 349 | else if (state->eof && state->strm.avail_in == 0) |
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| 350 | break; |
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| 351 | |
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| 352 | /* need more data to skip -- load up output buffer */ |
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| 353 | else { |
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| 354 | /* get more output, looking for header if required */ |
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| 355 | if (gz_make(state) == -1) |
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| 356 | return -1; |
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| 357 | } |
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| 358 | return 0; |
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| 359 | } |
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| 360 | |
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| 361 | /* -- see zlib.h -- */ |
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| 362 | int ZEXPORT gzread(file, buf, len) |
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| 363 | gzFile file; |
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| 364 | voidp buf; |
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| 365 | unsigned len; |
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| 366 | { |
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| 367 | unsigned got, n; |
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| 368 | gz_statep state; |
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| 369 | z_streamp strm; |
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| 370 | |
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| 371 | /* get internal structure */ |
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| 372 | if (file == NULL) |
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| 373 | return -1; |
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| 374 | state = (gz_statep)file; |
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| 375 | strm = &(state->strm); |
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| 376 | |
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| 377 | /* check that we're reading and that there's no error */ |
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| 378 | if (state->mode != GZ_READ || state->err != Z_OK) |
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| 379 | return -1; |
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| 380 | |
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| 381 | /* since an int is returned, make sure len fits in one, otherwise return |
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| 382 | with an error (this avoids the flaw in the interface) */ |
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| 383 | if ((int)len < 0) { |
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| 384 | gz_error(state, Z_BUF_ERROR, "requested length does not fit in int"); |
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| 385 | return -1; |
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| 386 | } |
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| 387 | |
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| 388 | /* if len is zero, avoid unnecessary operations */ |
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| 389 | if (len == 0) |
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| 390 | return 0; |
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| 391 | |
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| 392 | /* process a skip request */ |
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| 393 | if (state->seek) { |
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| 394 | state->seek = 0; |
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| 395 | if (gz_skip(state, state->skip) == -1) |
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| 396 | return -1; |
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| 397 | } |
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| 398 | |
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| 399 | /* get len bytes to buf, or less than len if at the end */ |
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| 400 | got = 0; |
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| 401 | do { |
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| 402 | /* first just try copying data from the output buffer */ |
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| 403 | if (state->have) { |
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| 404 | n = state->have > len ? len : state->have; |
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| 405 | memcpy(buf, state->next, n); |
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| 406 | state->next += n; |
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| 407 | state->have -= n; |
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| 408 | } |
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| 409 | |
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| 410 | /* output buffer empty -- return if we're at the end of the input */ |
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| 411 | else if (state->eof && strm->avail_in == 0) |
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| 412 | break; |
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| 413 | |
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| 414 | /* need output data -- for small len or new stream load up our output |
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| 415 | buffer */ |
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| 416 | else if (state->how == LOOK || len < (state->size << 1)) { |
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| 417 | /* get more output, looking for header if required */ |
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| 418 | if (gz_make(state) == -1) |
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| 419 | return -1; |
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| 420 | continue; /* no progress yet -- go back to memcpy() above */ |
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| 421 | /* the copy above assures that we will leave with space in the |
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| 422 | output buffer, allowing at least one gzungetc() to succeed */ |
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| 423 | } |
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| 424 | |
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| 425 | /* large len -- read directly into user buffer */ |
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| 426 | else if (state->how == COPY) { /* read directly */ |
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| 427 | if (gz_load(state, buf, len, &n) == -1) |
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| 428 | return -1; |
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| 429 | } |
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| 430 | |
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| 431 | /* large len -- decompress directly into user buffer */ |
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| 432 | else { /* state->how == GZIP */ |
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| 433 | strm->avail_out = len; |
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| 434 | strm->next_out = buf; |
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| 435 | if (gz_decomp(state) == -1) |
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| 436 | return -1; |
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| 437 | n = state->have; |
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| 438 | state->have = 0; |
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| 439 | } |
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| 440 | |
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| 441 | /* update progress */ |
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| 442 | len -= n; |
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| 443 | buf = (char *)buf + n; |
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| 444 | got += n; |
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| 445 | state->pos += n; |
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| 446 | } while (len); |
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| 447 | |
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| 448 | /* return number of bytes read into user buffer (will fit in int) */ |
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| 449 | return (int)got; |
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| 450 | } |
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| 451 | |
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| 452 | /* -- see zlib.h -- */ |
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| 453 | int ZEXPORT gzgetc(file) |
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| 454 | gzFile file; |
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| 455 | { |
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| 456 | int ret; |
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| 457 | unsigned char buf[1]; |
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| 458 | gz_statep state; |
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| 459 | |
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| 460 | /* get internal structure */ |
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| 461 | if (file == NULL) |
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| 462 | return -1; |
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| 463 | state = (gz_statep)file; |
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| 464 | |
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| 465 | /* check that we're reading and that there's no error */ |
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| 466 | if (state->mode != GZ_READ || state->err != Z_OK) |
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| 467 | return -1; |
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| 468 | |
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| 469 | /* try output buffer (no need to check for skip request) */ |
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| 470 | if (state->have) { |
---|
| 471 | state->have--; |
---|
| 472 | state->pos++; |
---|
| 473 | return *(state->next)++; |
---|
| 474 | } |
---|
| 475 | |
---|
| 476 | /* nothing there -- try gzread() */ |
---|
| 477 | ret = gzread(file, buf, 1); |
---|
| 478 | return ret < 1 ? -1 : buf[0]; |
---|
| 479 | } |
---|
| 480 | |
---|
| 481 | /* -- see zlib.h -- */ |
---|
| 482 | int ZEXPORT gzungetc(c, file) |
---|
| 483 | int c; |
---|
| 484 | gzFile file; |
---|
| 485 | { |
---|
| 486 | gz_statep state; |
---|
| 487 | |
---|
| 488 | /* get internal structure */ |
---|
| 489 | if (file == NULL) |
---|
| 490 | return -1; |
---|
| 491 | state = (gz_statep)file; |
---|
| 492 | |
---|
| 493 | /* check that we're reading and that there's no error */ |
---|
| 494 | if (state->mode != GZ_READ || state->err != Z_OK) |
---|
| 495 | return -1; |
---|
| 496 | |
---|
| 497 | /* process a skip request */ |
---|
| 498 | if (state->seek) { |
---|
| 499 | state->seek = 0; |
---|
| 500 | if (gz_skip(state, state->skip) == -1) |
---|
| 501 | return -1; |
---|
| 502 | } |
---|
| 503 | |
---|
| 504 | /* can't push EOF */ |
---|
| 505 | if (c < 0) |
---|
| 506 | return -1; |
---|
| 507 | |
---|
| 508 | /* if output buffer empty, put byte at end (allows more pushing) */ |
---|
| 509 | if (state->have == 0) { |
---|
| 510 | state->have = 1; |
---|
| 511 | state->next = state->out + (state->size << 1) - 1; |
---|
| 512 | state->next[0] = c; |
---|
| 513 | state->pos--; |
---|
| 514 | return c; |
---|
| 515 | } |
---|
| 516 | |
---|
| 517 | /* if no room, give up (must have already done a gzungetc()) */ |
---|
| 518 | if (state->have == (state->size << 1)) { |
---|
| 519 | gz_error(state, Z_BUF_ERROR, "out of room to push characters"); |
---|
| 520 | return -1; |
---|
| 521 | } |
---|
| 522 | |
---|
| 523 | /* slide output data if needed and insert byte before existing data */ |
---|
| 524 | if (state->next == state->out) { |
---|
| 525 | unsigned char *src = state->out + state->have; |
---|
| 526 | unsigned char *dest = state->out + (state->size << 1); |
---|
| 527 | while (src > state->out) |
---|
| 528 | *--dest = *--src; |
---|
| 529 | state->next = dest; |
---|
| 530 | } |
---|
| 531 | state->have++; |
---|
| 532 | state->next--; |
---|
| 533 | state->next[0] = c; |
---|
| 534 | state->pos--; |
---|
| 535 | return c; |
---|
| 536 | } |
---|
| 537 | |
---|
| 538 | /* -- see zlib.h -- */ |
---|
| 539 | char * ZEXPORT gzgets(file, buf, len) |
---|
| 540 | gzFile file; |
---|
| 541 | char *buf; |
---|
| 542 | int len; |
---|
| 543 | { |
---|
| 544 | unsigned left, n; |
---|
| 545 | char *str; |
---|
| 546 | unsigned char *eol; |
---|
| 547 | gz_statep state; |
---|
| 548 | |
---|
| 549 | /* check parameters and get internal structure */ |
---|
| 550 | if (file == NULL || buf == NULL || len < 1) |
---|
| 551 | return NULL; |
---|
| 552 | state = (gz_statep)file; |
---|
| 553 | |
---|
| 554 | /* check that we're reading and that there's no error */ |
---|
| 555 | if (state->mode != GZ_READ || state->err != Z_OK) |
---|
| 556 | return NULL; |
---|
| 557 | |
---|
| 558 | /* process a skip request */ |
---|
| 559 | if (state->seek) { |
---|
| 560 | state->seek = 0; |
---|
| 561 | if (gz_skip(state, state->skip) == -1) |
---|
| 562 | return NULL; |
---|
| 563 | } |
---|
| 564 | |
---|
| 565 | /* copy output bytes up to new line or len - 1, whichever comes first -- |
---|
| 566 | append a terminating zero to the string (we don't check for a zero in |
---|
| 567 | the contents, let the user worry about that) */ |
---|
| 568 | str = buf; |
---|
| 569 | left = (unsigned)len - 1; |
---|
| 570 | if (left) do { |
---|
| 571 | /* assure that something is in the output buffer */ |
---|
| 572 | if (state->have == 0) { |
---|
| 573 | if (gz_make(state) == -1) |
---|
| 574 | return NULL; /* error */ |
---|
| 575 | if (state->have == 0) { /* end of file */ |
---|
| 576 | if (buf == str) /* got bupkus */ |
---|
| 577 | return NULL; |
---|
| 578 | break; /* got something -- return it */ |
---|
| 579 | } |
---|
| 580 | } |
---|
| 581 | |
---|
| 582 | /* look for end-of-line in current output buffer */ |
---|
| 583 | n = state->have > left ? left : state->have; |
---|
| 584 | eol = memchr(state->next, '\n', n); |
---|
| 585 | if (eol != NULL) |
---|
| 586 | n = (unsigned)(eol - state->next) + 1; |
---|
| 587 | |
---|
| 588 | /* copy through end-of-line, or remainder if not found */ |
---|
| 589 | memcpy(buf, state->next, n); |
---|
| 590 | state->have -= n; |
---|
| 591 | state->next += n; |
---|
| 592 | state->pos += n; |
---|
| 593 | left -= n; |
---|
| 594 | buf += n; |
---|
| 595 | } while (left && eol == NULL); |
---|
| 596 | |
---|
| 597 | /* found end-of-line or out of space -- terminate string and return it */ |
---|
| 598 | buf[0] = 0; |
---|
| 599 | return str; |
---|
| 600 | } |
---|
| 601 | |
---|
| 602 | /* -- see zlib.h -- */ |
---|
| 603 | int ZEXPORT gzdirect(file) |
---|
| 604 | gzFile file; |
---|
| 605 | { |
---|
| 606 | gz_statep state; |
---|
| 607 | |
---|
| 608 | /* get internal structure */ |
---|
| 609 | if (file == NULL) |
---|
| 610 | return 0; |
---|
| 611 | state = (gz_statep)file; |
---|
| 612 | |
---|
| 613 | /* check that we're reading */ |
---|
| 614 | if (state->mode != GZ_READ) |
---|
| 615 | return 0; |
---|
| 616 | |
---|
| 617 | /* if the state is not known, but we can find out, then do so (this is |
---|
| 618 | mainly for right after a gzopen() or gzdopen()) */ |
---|
| 619 | if (state->how == LOOK && state->have == 0) |
---|
| 620 | (void)gz_head(state); |
---|
| 621 | |
---|
| 622 | /* return 1 if reading direct, 0 if decompressing a gzip stream */ |
---|
| 623 | return state->direct; |
---|
| 624 | } |
---|
| 625 | |
---|
| 626 | /* -- see zlib.h -- */ |
---|
| 627 | int ZEXPORT gzclose_r(file) |
---|
| 628 | gzFile file; |
---|
| 629 | { |
---|
| 630 | int ret; |
---|
| 631 | gz_statep state; |
---|
| 632 | |
---|
| 633 | /* get internal structure */ |
---|
| 634 | if (file == NULL) |
---|
| 635 | return Z_STREAM_ERROR; |
---|
| 636 | state = (gz_statep)file; |
---|
| 637 | |
---|
| 638 | /* check that we're reading */ |
---|
| 639 | if (state->mode != GZ_READ) |
---|
| 640 | return Z_STREAM_ERROR; |
---|
| 641 | |
---|
| 642 | /* free memory and close file */ |
---|
| 643 | if (state->size) { |
---|
| 644 | inflateEnd(&(state->strm)); |
---|
| 645 | free(state->out); |
---|
| 646 | free(state->in); |
---|
| 647 | } |
---|
| 648 | gz_error(state, Z_OK, NULL); |
---|
| 649 | free(state->path); |
---|
| 650 | ret = close(state->fd); |
---|
| 651 | free(state); |
---|
| 652 | return ret ? Z_ERRNO : Z_OK; |
---|
| 653 | } |
---|