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1 /* gzio.c -- IO on .gz files |
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2 * Copyright (C) 1995-2005 Jean-loup Gailly. |
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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 * Compile this file with -DNO_GZCOMPRESS to avoid the compression code. |
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6 */ |
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7 |
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8 /* @(#) $Id$ */ |
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9 |
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10 #include <stdio.h> |
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11 |
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12 #include "zutil.h" |
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13 |
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14 #ifdef NO_DEFLATE /* for compatibility with old definition */ |
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15 # define NO_GZCOMPRESS |
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16 #endif |
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17 |
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18 #ifndef NO_DUMMY_DECL |
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19 struct internal_state {int dummy;}; /* for buggy compilers */ |
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20 #endif |
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21 |
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22 #ifndef Z_BUFSIZE |
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23 # ifdef MAXSEG_64K |
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24 # define Z_BUFSIZE 4096 /* minimize memory usage for 16-bit DOS */ |
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25 # else |
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26 # define Z_BUFSIZE 16384 |
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27 # endif |
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28 #endif |
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29 #ifndef Z_PRINTF_BUFSIZE |
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30 # define Z_PRINTF_BUFSIZE 4096 |
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31 #endif |
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32 |
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33 #ifdef __MVS__ |
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34 # pragma map (fdopen , "\174\174FDOPEN") |
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35 FILE *fdopen(int, const char *); |
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36 #endif |
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37 |
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38 #ifndef STDC |
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39 extern voidp malloc OF((uInt size)); |
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40 extern void free OF((voidpf ptr)); |
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41 #endif |
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42 |
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43 #define ALLOC(size) malloc(size) |
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44 #define TRYFREE(p) {if (p) free(p);} |
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45 |
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46 static int const gz_magic[2] = {0x1f, 0x8b}; /* gzip magic header */ |
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47 |
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48 /* gzip flag byte */ |
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49 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ |
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50 #define HEAD_CRC 0x02 /* bit 1 set: header CRC present */ |
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51 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ |
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52 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ |
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53 #define COMMENT 0x10 /* bit 4 set: file comment present */ |
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54 #define RESERVED 0xE0 /* bits 5..7: reserved */ |
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55 |
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56 typedef struct gz_stream { |
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57 z_stream stream; |
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58 int z_err; /* error code for last stream operation */ |
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59 int z_eof; /* set if end of input file */ |
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60 FILE *file; /* .gz file */ |
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61 Byte *inbuf; /* input buffer */ |
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62 Byte *outbuf; /* output buffer */ |
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63 uLong crc; /* crc32 of uncompressed data */ |
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64 char *msg; /* error message */ |
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65 char *path; /* path name for debugging only */ |
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66 int transparent; /* 1 if input file is not a .gz file */ |
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67 char mode; /* 'w' or 'r' */ |
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68 z_off_t start; /* start of compressed data in file (header skipped) */ |
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69 z_off_t in; /* bytes into deflate or inflate */ |
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70 z_off_t out; /* bytes out of deflate or inflate */ |
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71 int back; /* one character push-back */ |
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72 int last; /* true if push-back is last character */ |
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73 } gz_stream; |
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74 |
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75 |
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76 local gzFile gz_open OF((const char *path, const char *mode, int fd)); |
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77 local int do_flush OF((gzFile file, int flush)); |
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78 local int get_byte OF((gz_stream *s)); |
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79 local void check_header OF((gz_stream *s)); |
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80 local int destroy OF((gz_stream *s)); |
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81 local void putLong OF((FILE *file, uLong x)); |
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82 local uLong getLong OF((gz_stream *s)); |
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83 |
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84 /* =========================================================================== |
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85 Opens a gzip (.gz) file for reading or writing. The mode parameter |
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86 is as in fopen ("rb" or "wb"). The file is given either by file descriptor |
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87 or path name (if fd == -1). |
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88 gz_open returns NULL if the file could not be opened or if there was |
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89 insufficient memory to allocate the (de)compression state; errno |
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90 can be checked to distinguish the two cases (if errno is zero, the |
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91 zlib error is Z_MEM_ERROR). |
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92 */ |
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93 local gzFile gz_open (path, mode, fd) |
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94 const char *path; |
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95 const char *mode; |
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96 int fd; |
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97 { |
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98 int err; |
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99 int level = Z_DEFAULT_COMPRESSION; /* compression level */ |
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100 int strategy = Z_DEFAULT_STRATEGY; /* compression strategy */ |
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101 char *p = (char*)mode; |
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102 gz_stream *s; |
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103 char fmode[80]; /* copy of mode, without the compression level */ |
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104 char *m = fmode; |
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105 |
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106 if (!path || !mode) return Z_NULL; |
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107 |
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108 s = (gz_stream *)ALLOC(sizeof(gz_stream)); |
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109 if (!s) return Z_NULL; |
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110 |
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111 s->stream.zalloc = (alloc_func)0; |
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112 s->stream.zfree = (free_func)0; |
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113 s->stream.opaque = (voidpf)0; |
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114 s->stream.next_in = s->inbuf = Z_NULL; |
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115 s->stream.next_out = s->outbuf = Z_NULL; |
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116 s->stream.avail_in = s->stream.avail_out = 0; |
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117 s->file = NULL; |
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118 s->z_err = Z_OK; |
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119 s->z_eof = 0; |
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120 s->in = 0; |
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121 s->out = 0; |
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122 s->back = EOF; |
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123 s->crc = crc32(0L, Z_NULL, 0); |
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124 s->msg = NULL; |
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125 s->transparent = 0; |
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126 |
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127 s->path = (char*)ALLOC(strlen(path)+1); |
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128 if (s->path == NULL) { |
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129 return destroy(s), (gzFile)Z_NULL; |
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130 } |
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131 strcpy(s->path, path); /* do this early for debugging */ |
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132 |
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133 s->mode = '\0'; |
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134 do { |
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135 if (*p == 'r') s->mode = 'r'; |
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136 if (*p == 'w' || *p == 'a') s->mode = 'w'; |
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137 if (*p >= '0' && *p <= '9') { |
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138 level = *p - '0'; |
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139 } else if (*p == 'f') { |
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140 strategy = Z_FILTERED; |
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141 } else if (*p == 'h') { |
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142 strategy = Z_HUFFMAN_ONLY; |
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143 } else if (*p == 'R') { |
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144 strategy = Z_RLE; |
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145 } else { |
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146 *m++ = *p; /* copy the mode */ |
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147 } |
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148 } while (*p++ && m != fmode + sizeof(fmode)); |
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149 if (s->mode == '\0') return destroy(s), (gzFile)Z_NULL; |
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150 |
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151 if (s->mode == 'w') { |
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152 #ifdef NO_GZCOMPRESS |
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153 err = Z_STREAM_ERROR; |
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154 #else |
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155 err = deflateInit2(&(s->stream), level, |
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156 Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL, strategy); |
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157 /* windowBits is passed < 0 to suppress zlib header */ |
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158 |
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159 s->stream.next_out = s->outbuf = (Byte*)ALLOC(Z_BUFSIZE); |
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160 #endif |
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161 if (err != Z_OK || s->outbuf == Z_NULL) { |
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162 return destroy(s), (gzFile)Z_NULL; |
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163 } |
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164 } else { |
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165 s->stream.next_in = s->inbuf = (Byte*)ALLOC(Z_BUFSIZE); |
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166 |
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167 err = inflateInit2(&(s->stream), -MAX_WBITS); |
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168 /* windowBits is passed < 0 to tell that there is no zlib header. |
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169 * Note that in this case inflate *requires* an extra "dummy" byte |
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170 * after the compressed stream in order to complete decompression and |
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171 * return Z_STREAM_END. Here the gzip CRC32 ensures that 4 bytes are |
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172 * present after the compressed stream. |
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173 */ |
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174 if (err != Z_OK || s->inbuf == Z_NULL) { |
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175 return destroy(s), (gzFile)Z_NULL; |
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176 } |
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177 } |
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178 s->stream.avail_out = Z_BUFSIZE; |
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179 |
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180 errno = 0; |
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181 s->file = fd < 0 ? F_OPEN(path, fmode) : (FILE*)fdopen(fd, fmode); |
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182 |
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183 if (s->file == NULL) { |
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184 return destroy(s), (gzFile)Z_NULL; |
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185 } |
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186 if (s->mode == 'w') { |
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187 /* Write a very simple .gz header: |
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188 */ |
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189 fprintf(s->file, "%c%c%c%c%c%c%c%c%c%c", gz_magic[0], gz_magic[1], |
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190 Z_DEFLATED, 0 /*flags*/, 0,0,0,0 /*time*/, 0 /*xflags*/, OS_CODE); |
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191 s->start = 10L; |
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192 /* We use 10L instead of ftell(s->file) to because ftell causes an |
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193 * fflush on some systems. This version of the library doesn't use |
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194 * start anyway in write mode, so this initialization is not |
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195 * necessary. |
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196 */ |
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197 } else { |
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198 check_header(s); /* skip the .gz header */ |
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199 s->start = ftell(s->file) - s->stream.avail_in; |
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200 } |
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201 |
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202 return (gzFile)s; |
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203 } |
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204 |
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205 /* =========================================================================== |
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206 Opens a gzip (.gz) file for reading or writing. |
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207 */ |
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208 gzFile ZEXPORT gzopen (path, mode) |
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209 const char *path; |
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210 const char *mode; |
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211 { |
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212 return gz_open (path, mode, -1); |
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213 } |
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214 |
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215 /* =========================================================================== |
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216 Associate a gzFile with the file descriptor fd. fd is not dup'ed here |
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217 to mimic the behavio(u)r of fdopen. |
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218 */ |
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219 gzFile ZEXPORT gzdopen (fd, mode) |
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220 int fd; |
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221 const char *mode; |
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222 { |
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223 char name[46]; /* allow for up to 128-bit integers */ |
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224 |
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225 if (fd < 0) return (gzFile)Z_NULL; |
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226 sprintf(name, "<fd:%d>", fd); /* for debugging */ |
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227 |
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228 return gz_open (name, mode, fd); |
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229 } |
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230 |
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231 /* =========================================================================== |
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232 * Update the compression level and strategy |
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233 */ |
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234 int ZEXPORT gzsetparams (file, level, strategy) |
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235 gzFile file; |
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236 int level; |
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237 int strategy; |
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238 { |
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239 gz_stream *s = (gz_stream*)file; |
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240 |
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241 if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR; |
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242 |
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243 /* Make room to allow flushing */ |
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244 if (s->stream.avail_out == 0) { |
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245 |
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246 s->stream.next_out = s->outbuf; |
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247 if (fwrite(s->outbuf, 1, Z_BUFSIZE, s->file) != Z_BUFSIZE) { |
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248 s->z_err = Z_ERRNO; |
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249 } |
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250 s->stream.avail_out = Z_BUFSIZE; |
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251 } |
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252 |
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253 return deflateParams (&(s->stream), level, strategy); |
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254 } |
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255 |
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256 /* =========================================================================== |
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257 Read a byte from a gz_stream; update next_in and avail_in. Return EOF |
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258 for end of file. |
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259 IN assertion: the stream s has been sucessfully opened for reading. |
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260 */ |
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261 local int get_byte(s) |
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262 gz_stream *s; |
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263 { |
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264 if (s->z_eof) return EOF; |
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265 if (s->stream.avail_in == 0) { |
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266 errno = 0; |
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267 s->stream.avail_in = (uInt)fread(s->inbuf, 1, Z_BUFSIZE, s->file); |
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268 if (s->stream.avail_in == 0) { |
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269 s->z_eof = 1; |
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270 if (ferror(s->file)) s->z_err = Z_ERRNO; |
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271 return EOF; |
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272 } |
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273 s->stream.next_in = s->inbuf; |
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274 } |
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275 s->stream.avail_in--; |
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276 return *(s->stream.next_in)++; |
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277 } |
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278 |
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279 /* =========================================================================== |
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280 Check the gzip header of a gz_stream opened for reading. Set the stream |
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281 mode to transparent if the gzip magic header is not present; set s->err |
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282 to Z_DATA_ERROR if the magic header is present but the rest of the header |
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283 is incorrect. |
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284 IN assertion: the stream s has already been created sucessfully; |
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285 s->stream.avail_in is zero for the first time, but may be non-zero |
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286 for concatenated .gz files. |
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287 */ |
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288 local void check_header(s) |
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289 gz_stream *s; |
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290 { |
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291 int method; /* method byte */ |
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292 int flags; /* flags byte */ |
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293 uInt len; |
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294 int c; |
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295 |
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296 /* Assure two bytes in the buffer so we can peek ahead -- handle case |
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297 where first byte of header is at the end of the buffer after the last |
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298 gzip segment */ |
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299 len = s->stream.avail_in; |
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300 if (len < 2) { |
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301 if (len) s->inbuf[0] = s->stream.next_in[0]; |
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302 errno = 0; |
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303 len = (uInt)fread(s->inbuf + len, 1, Z_BUFSIZE >> len, s->file); |
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304 if (len == 0 && ferror(s->file)) s->z_err = Z_ERRNO; |
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305 s->stream.avail_in += len; |
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306 s->stream.next_in = s->inbuf; |
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307 if (s->stream.avail_in < 2) { |
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308 s->transparent = s->stream.avail_in; |
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309 return; |
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310 } |
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311 } |
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312 |
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313 /* Peek ahead to check the gzip magic header */ |
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314 if (s->stream.next_in[0] != gz_magic[0] || |
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315 s->stream.next_in[1] != gz_magic[1]) { |
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316 s->transparent = 1; |
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317 return; |
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318 } |
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319 s->stream.avail_in -= 2; |
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320 s->stream.next_in += 2; |
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321 |
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322 /* Check the rest of the gzip header */ |
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323 method = get_byte(s); |
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324 flags = get_byte(s); |
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325 if (method != Z_DEFLATED || (flags & RESERVED) != 0) { |
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326 s->z_err = Z_DATA_ERROR; |
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327 return; |
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328 } |
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329 |
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330 /* Discard time, xflags and OS code: */ |
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331 for (len = 0; len < 6; len++) (void)get_byte(s); |
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332 |
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333 if ((flags & EXTRA_FIELD) != 0) { /* skip the extra field */ |
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334 len = (uInt)get_byte(s); |
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335 len += ((uInt)get_byte(s))<<8; |
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336 /* len is garbage if EOF but the loop below will quit anyway */ |
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337 while (len-- != 0 && get_byte(s) != EOF) ; |
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338 } |
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339 if ((flags & ORIG_NAME) != 0) { /* skip the original file name */ |
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340 while ((c = get_byte(s)) != 0 && c != EOF) ; |
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341 } |
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342 if ((flags & COMMENT) != 0) { /* skip the .gz file comment */ |
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343 while ((c = get_byte(s)) != 0 && c != EOF) ; |
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344 } |
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345 if ((flags & HEAD_CRC) != 0) { /* skip the header crc */ |
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346 for (len = 0; len < 2; len++) (void)get_byte(s); |
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347 } |
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348 s->z_err = s->z_eof ? Z_DATA_ERROR : Z_OK; |
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349 } |
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350 |
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351 /* =========================================================================== |
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352 * Cleanup then free the given gz_stream. Return a zlib error code. |
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353 Try freeing in the reverse order of allocations. |
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354 */ |
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355 local int destroy (s) |
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356 gz_stream *s; |
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357 { |
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358 int err = Z_OK; |
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359 |
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360 if (!s) return Z_STREAM_ERROR; |
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361 |
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362 TRYFREE(s->msg); |
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363 |
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364 if (s->stream.state != NULL) { |
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365 if (s->mode == 'w') { |
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366 #ifdef NO_GZCOMPRESS |
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367 err = Z_STREAM_ERROR; |
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368 #else |
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369 err = deflateEnd(&(s->stream)); |
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370 #endif |
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371 } else if (s->mode == 'r') { |
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372 err = inflateEnd(&(s->stream)); |
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373 } |
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374 } |
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375 if (s->file != NULL && fclose(s->file)) { |
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376 #ifdef ESPIPE |
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377 if (errno != ESPIPE) /* fclose is broken for pipes in HP/UX */ |
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378 #endif |
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379 err = Z_ERRNO; |
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380 } |
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381 if (s->z_err < 0) err = s->z_err; |
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382 |
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383 TRYFREE(s->inbuf); |
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384 TRYFREE(s->outbuf); |
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385 TRYFREE(s->path); |
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386 TRYFREE(s); |
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387 return err; |
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388 } |
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389 |
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390 /* =========================================================================== |
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391 Reads the given number of uncompressed bytes from the compressed file. |
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392 gzread returns the number of bytes actually read (0 for end of file). |
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393 */ |
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394 int ZEXPORT gzread (file, buf, len) |
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395 gzFile file; |
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396 voidp buf; |
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397 unsigned len; |
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398 { |
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399 gz_stream *s = (gz_stream*)file; |
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400 Bytef *start = (Bytef*)buf; /* starting point for crc computation */ |
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401 Byte *next_out; /* == stream.next_out but not forced far (for MSDOS) */ |
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402 |
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403 if (s == NULL || s->mode != 'r') return Z_STREAM_ERROR; |
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404 |
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405 if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO) return -1; |
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406 if (s->z_err == Z_STREAM_END) return 0; /* EOF */ |
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407 |
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408 next_out = (Byte*)buf; |
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409 s->stream.next_out = (Bytef*)buf; |
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410 s->stream.avail_out = len; |
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411 |
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412 if (s->stream.avail_out && s->back != EOF) { |
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413 *next_out++ = s->back; |
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414 s->stream.next_out++; |
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415 s->stream.avail_out--; |
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416 s->back = EOF; |
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417 s->out++; |
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418 start++; |
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419 if (s->last) { |
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420 s->z_err = Z_STREAM_END; |
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421 return 1; |
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422 } |
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423 } |
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424 |
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425 while (s->stream.avail_out != 0) { |
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426 |
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427 if (s->transparent) { |
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428 /* Copy first the lookahead bytes: */ |
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429 uInt n = s->stream.avail_in; |
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430 if (n > s->stream.avail_out) n = s->stream.avail_out; |
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431 if (n > 0) { |
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432 zmemcpy(s->stream.next_out, s->stream.next_in, n); |
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433 next_out += n; |
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434 s->stream.next_out = next_out; |
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435 s->stream.next_in += n; |
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436 s->stream.avail_out -= n; |
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437 s->stream.avail_in -= n; |
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438 } |
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439 if (s->stream.avail_out > 0) { |
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440 s->stream.avail_out -= |
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441 (uInt)fread(next_out, 1, s->stream.avail_out, s->file); |
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442 } |
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443 len -= s->stream.avail_out; |
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444 s->in += len; |
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445 s->out += len; |
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446 if (len == 0) s->z_eof = 1; |
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447 return (int)len; |
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448 } |
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449 if (s->stream.avail_in == 0 && !s->z_eof) { |
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450 |
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451 errno = 0; |
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452 s->stream.avail_in = (uInt)fread(s->inbuf, 1, Z_BUFSIZE, s->file); |
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453 if (s->stream.avail_in == 0) { |
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454 s->z_eof = 1; |
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455 if (ferror(s->file)) { |
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456 s->z_err = Z_ERRNO; |
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457 break; |
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458 } |
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459 } |
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460 s->stream.next_in = s->inbuf; |
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461 } |
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462 s->in += s->stream.avail_in; |
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463 s->out += s->stream.avail_out; |
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464 s->z_err = inflate(&(s->stream), Z_NO_FLUSH); |
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465 s->in -= s->stream.avail_in; |
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466 s->out -= s->stream.avail_out; |
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467 |
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468 if (s->z_err == Z_STREAM_END) { |
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469 /* Check CRC and original size */ |
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470 s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start)); |
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471 start = s->stream.next_out; |
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472 |
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473 if (getLong(s) != s->crc) { |
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474 s->z_err = Z_DATA_ERROR; |
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475 } else { |
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476 (void)getLong(s); |
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477 /* The uncompressed length returned by above getlong() may be |
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478 * different from s->out in case of concatenated .gz files. |
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479 * Check for such files: |
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480 */ |
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481 check_header(s); |
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482 if (s->z_err == Z_OK) { |
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483 inflateReset(&(s->stream)); |
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484 s->crc = crc32(0L, Z_NULL, 0); |
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485 } |
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486 } |
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487 } |
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488 if (s->z_err != Z_OK || s->z_eof) break; |
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489 } |
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490 s->crc = crc32(s->crc, start, (uInt)(s->stream.next_out - start)); |
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491 |
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492 if (len == s->stream.avail_out && |
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493 (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO)) |
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494 return -1; |
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495 return (int)(len - s->stream.avail_out); |
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496 } |
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497 |
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498 |
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499 /* =========================================================================== |
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500 Reads one byte from the compressed file. gzgetc returns this byte |
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501 or -1 in case of end of file or error. |
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502 */ |
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503 int ZEXPORT gzgetc(file) |
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504 gzFile file; |
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505 { |
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506 unsigned char c; |
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507 |
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508 return gzread(file, &c, 1) == 1 ? c : -1; |
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509 } |
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510 |
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511 |
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512 /* =========================================================================== |
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513 Push one byte back onto the stream. |
|
514 */ |
|
515 int ZEXPORT gzungetc(c, file) |
|
516 int c; |
|
517 gzFile file; |
|
518 { |
|
519 gz_stream *s = (gz_stream*)file; |
|
520 |
|
521 if (s == NULL || s->mode != 'r' || c == EOF || s->back != EOF) return EOF; |
|
522 s->back = c; |
|
523 s->out--; |
|
524 s->last = (s->z_err == Z_STREAM_END); |
|
525 if (s->last) s->z_err = Z_OK; |
|
526 s->z_eof = 0; |
|
527 return c; |
|
528 } |
|
529 |
|
530 |
|
531 /* =========================================================================== |
|
532 Reads bytes from the compressed file until len-1 characters are |
|
533 read, or a newline character is read and transferred to buf, or an |
|
534 end-of-file condition is encountered. The string is then terminated |
|
535 with a null character. |
|
536 gzgets returns buf, or Z_NULL in case of error. |
|
537 |
|
538 The current implementation is not optimized at all. |
|
539 */ |
|
540 char * ZEXPORT gzgets(file, buf, len) |
|
541 gzFile file; |
|
542 char *buf; |
|
543 int len; |
|
544 { |
|
545 char *b = buf; |
|
546 if (buf == Z_NULL || len <= 0) return Z_NULL; |
|
547 |
|
548 while (--len > 0 && gzread(file, buf, 1) == 1 && *buf++ != '\n') ; |
|
549 *buf = '\0'; |
|
550 return b == buf && len > 0 ? Z_NULL : b; |
|
551 } |
|
552 |
|
553 |
|
554 #ifndef NO_GZCOMPRESS |
|
555 /* =========================================================================== |
|
556 Writes the given number of uncompressed bytes into the compressed file. |
|
557 gzwrite returns the number of bytes actually written (0 in case of error). |
|
558 */ |
|
559 int ZEXPORT gzwrite (file, buf, len) |
|
560 gzFile file; |
|
561 voidpc buf; |
|
562 unsigned len; |
|
563 { |
|
564 gz_stream *s = (gz_stream*)file; |
|
565 |
|
566 if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR; |
|
567 |
|
568 s->stream.next_in = (Bytef*)buf; |
|
569 s->stream.avail_in = len; |
|
570 |
|
571 while (s->stream.avail_in != 0) { |
|
572 |
|
573 if (s->stream.avail_out == 0) { |
|
574 |
|
575 s->stream.next_out = s->outbuf; |
|
576 if (fwrite(s->outbuf, 1, Z_BUFSIZE, s->file) != Z_BUFSIZE) { |
|
577 s->z_err = Z_ERRNO; |
|
578 break; |
|
579 } |
|
580 s->stream.avail_out = Z_BUFSIZE; |
|
581 } |
|
582 s->in += s->stream.avail_in; |
|
583 s->out += s->stream.avail_out; |
|
584 s->z_err = deflate(&(s->stream), Z_NO_FLUSH); |
|
585 s->in -= s->stream.avail_in; |
|
586 s->out -= s->stream.avail_out; |
|
587 if (s->z_err != Z_OK) break; |
|
588 } |
|
589 s->crc = crc32(s->crc, (const Bytef *)buf, len); |
|
590 |
|
591 return (int)(len - s->stream.avail_in); |
|
592 } |
|
593 |
|
594 |
|
595 /* =========================================================================== |
|
596 Converts, formats, and writes the args to the compressed file under |
|
597 control of the format string, as in fprintf. gzprintf returns the number of |
|
598 uncompressed bytes actually written (0 in case of error). |
|
599 */ |
|
600 #ifdef STDC |
|
601 #include <stdarg.h> |
|
602 |
|
603 int ZEXPORTVA gzprintf (gzFile file, const char *format, /* args */ ...) |
|
604 { |
|
605 char buf[Z_PRINTF_BUFSIZE]; |
|
606 va_list va; |
|
607 int len; |
|
608 |
|
609 buf[sizeof(buf) - 1] = 0; |
|
610 va_start(va, format); |
|
611 #ifdef NO_vsnprintf |
|
612 # ifdef HAS_vsprintf_void |
|
613 (void)vsprintf(buf, format, va); |
|
614 va_end(va); |
|
615 for (len = 0; len < sizeof(buf); len++) |
|
616 if (buf[len] == 0) break; |
|
617 # else |
|
618 len = vsprintf(buf, format, va); |
|
619 va_end(va); |
|
620 # endif |
|
621 #else |
|
622 # ifdef HAS_vsnprintf_void |
|
623 (void)vsnprintf(buf, sizeof(buf), format, va); |
|
624 va_end(va); |
|
625 len = strlen(buf); |
|
626 # else |
|
627 len = vsnprintf(buf, sizeof(buf), format, va); |
|
628 va_end(va); |
|
629 # endif |
|
630 #endif |
|
631 if (len <= 0 || len >= (int)sizeof(buf) || buf[sizeof(buf) - 1] != 0) |
|
632 return 0; |
|
633 return gzwrite(file, buf, (unsigned)len); |
|
634 } |
|
635 #else /* not ANSI C */ |
|
636 |
|
637 int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, |
|
638 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20) |
|
639 gzFile file; |
|
640 const char *format; |
|
641 int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, |
|
642 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20; |
|
643 { |
|
644 char buf[Z_PRINTF_BUFSIZE]; |
|
645 int len; |
|
646 |
|
647 buf[sizeof(buf) - 1] = 0; |
|
648 #ifdef NO_snprintf |
|
649 # ifdef HAS_sprintf_void |
|
650 sprintf(buf, format, a1, a2, a3, a4, a5, a6, a7, a8, |
|
651 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); |
|
652 for (len = 0; len < sizeof(buf); len++) |
|
653 if (buf[len] == 0) break; |
|
654 # else |
|
655 len = sprintf(buf, format, a1, a2, a3, a4, a5, a6, a7, a8, |
|
656 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); |
|
657 # endif |
|
658 #else |
|
659 # ifdef HAS_snprintf_void |
|
660 snprintf(buf, sizeof(buf), format, a1, a2, a3, a4, a5, a6, a7, a8, |
|
661 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); |
|
662 len = strlen(buf); |
|
663 # else |
|
664 len = snprintf(buf, sizeof(buf), format, a1, a2, a3, a4, a5, a6, a7, a8, |
|
665 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20); |
|
666 # endif |
|
667 #endif |
|
668 if (len <= 0 || len >= sizeof(buf) || buf[sizeof(buf) - 1] != 0) |
|
669 return 0; |
|
670 return gzwrite(file, buf, len); |
|
671 } |
|
672 #endif |
|
673 |
|
674 /* =========================================================================== |
|
675 Writes c, converted to an unsigned char, into the compressed file. |
|
676 gzputc returns the value that was written, or -1 in case of error. |
|
677 */ |
|
678 int ZEXPORT gzputc(file, c) |
|
679 gzFile file; |
|
680 int c; |
|
681 { |
|
682 unsigned char cc = (unsigned char) c; /* required for big endian systems */ |
|
683 |
|
684 return gzwrite(file, &cc, 1) == 1 ? (int)cc : -1; |
|
685 } |
|
686 |
|
687 |
|
688 /* =========================================================================== |
|
689 Writes the given null-terminated string to the compressed file, excluding |
|
690 the terminating null character. |
|
691 gzputs returns the number of characters written, or -1 in case of error. |
|
692 */ |
|
693 int ZEXPORT gzputs(file, s) |
|
694 gzFile file; |
|
695 const char *s; |
|
696 { |
|
697 return gzwrite(file, (char*)s, (unsigned)strlen(s)); |
|
698 } |
|
699 |
|
700 |
|
701 /* =========================================================================== |
|
702 Flushes all pending output into the compressed file. The parameter |
|
703 flush is as in the deflate() function. |
|
704 */ |
|
705 local int do_flush (file, flush) |
|
706 gzFile file; |
|
707 int flush; |
|
708 { |
|
709 uInt len; |
|
710 int done = 0; |
|
711 gz_stream *s = (gz_stream*)file; |
|
712 |
|
713 if (s == NULL || s->mode != 'w') return Z_STREAM_ERROR; |
|
714 |
|
715 s->stream.avail_in = 0; /* should be zero already anyway */ |
|
716 |
|
717 for (;;) { |
|
718 len = Z_BUFSIZE - s->stream.avail_out; |
|
719 |
|
720 if (len != 0) { |
|
721 if ((uInt)fwrite(s->outbuf, 1, len, s->file) != len) { |
|
722 s->z_err = Z_ERRNO; |
|
723 return Z_ERRNO; |
|
724 } |
|
725 s->stream.next_out = s->outbuf; |
|
726 s->stream.avail_out = Z_BUFSIZE; |
|
727 } |
|
728 if (done) break; |
|
729 s->out += s->stream.avail_out; |
|
730 s->z_err = deflate(&(s->stream), flush); |
|
731 s->out -= s->stream.avail_out; |
|
732 |
|
733 /* Ignore the second of two consecutive flushes: */ |
|
734 if (len == 0 && s->z_err == Z_BUF_ERROR) s->z_err = Z_OK; |
|
735 |
|
736 /* deflate has finished flushing only when it hasn't used up |
|
737 * all the available space in the output buffer: |
|
738 */ |
|
739 done = (s->stream.avail_out != 0 || s->z_err == Z_STREAM_END); |
|
740 |
|
741 if (s->z_err != Z_OK && s->z_err != Z_STREAM_END) break; |
|
742 } |
|
743 return s->z_err == Z_STREAM_END ? Z_OK : s->z_err; |
|
744 } |
|
745 |
|
746 int ZEXPORT gzflush (file, flush) |
|
747 gzFile file; |
|
748 int flush; |
|
749 { |
|
750 gz_stream *s = (gz_stream*)file; |
|
751 int err = do_flush (file, flush); |
|
752 |
|
753 if (err) return err; |
|
754 fflush(s->file); |
|
755 return s->z_err == Z_STREAM_END ? Z_OK : s->z_err; |
|
756 } |
|
757 #endif /* NO_GZCOMPRESS */ |
|
758 |
|
759 /* =========================================================================== |
|
760 Sets the starting position for the next gzread or gzwrite on the given |
|
761 compressed file. The offset represents a number of bytes in the |
|
762 gzseek returns the resulting offset location as measured in bytes from |
|
763 the beginning of the uncompressed stream, or -1 in case of error. |
|
764 SEEK_END is not implemented, returns error. |
|
765 In this version of the library, gzseek can be extremely slow. |
|
766 */ |
|
767 z_off_t ZEXPORT gzseek (file, offset, whence) |
|
768 gzFile file; |
|
769 z_off_t offset; |
|
770 int whence; |
|
771 { |
|
772 gz_stream *s = (gz_stream*)file; |
|
773 |
|
774 if (s == NULL || whence == SEEK_END || |
|
775 s->z_err == Z_ERRNO || s->z_err == Z_DATA_ERROR) { |
|
776 return -1L; |
|
777 } |
|
778 |
|
779 if (s->mode == 'w') { |
|
780 #ifdef NO_GZCOMPRESS |
|
781 return -1L; |
|
782 #else |
|
783 if (whence == SEEK_SET) { |
|
784 offset -= s->in; |
|
785 } |
|
786 if (offset < 0) return -1L; |
|
787 |
|
788 /* At this point, offset is the number of zero bytes to write. */ |
|
789 if (s->inbuf == Z_NULL) { |
|
790 s->inbuf = (Byte*)ALLOC(Z_BUFSIZE); /* for seeking */ |
|
791 if (s->inbuf == Z_NULL) return -1L; |
|
792 zmemzero(s->inbuf, Z_BUFSIZE); |
|
793 } |
|
794 while (offset > 0) { |
|
795 uInt size = Z_BUFSIZE; |
|
796 if (offset < Z_BUFSIZE) size = (uInt)offset; |
|
797 |
|
798 size = gzwrite(file, s->inbuf, size); |
|
799 if (size == 0) return -1L; |
|
800 |
|
801 offset -= size; |
|
802 } |
|
803 return s->in; |
|
804 #endif |
|
805 } |
|
806 /* Rest of function is for reading only */ |
|
807 |
|
808 /* compute absolute position */ |
|
809 if (whence == SEEK_CUR) { |
|
810 offset += s->out; |
|
811 } |
|
812 if (offset < 0) return -1L; |
|
813 |
|
814 if (s->transparent) { |
|
815 /* map to fseek */ |
|
816 s->back = EOF; |
|
817 s->stream.avail_in = 0; |
|
818 s->stream.next_in = s->inbuf; |
|
819 if (fseek(s->file, offset, SEEK_SET) < 0) return -1L; |
|
820 |
|
821 s->in = s->out = offset; |
|
822 return offset; |
|
823 } |
|
824 |
|
825 /* For a negative seek, rewind and use positive seek */ |
|
826 if (offset >= s->out) { |
|
827 offset -= s->out; |
|
828 } else if (gzrewind(file) < 0) { |
|
829 return -1L; |
|
830 } |
|
831 /* offset is now the number of bytes to skip. */ |
|
832 |
|
833 if (offset != 0 && s->outbuf == Z_NULL) { |
|
834 s->outbuf = (Byte*)ALLOC(Z_BUFSIZE); |
|
835 if (s->outbuf == Z_NULL) return -1L; |
|
836 } |
|
837 if (offset && s->back != EOF) { |
|
838 s->back = EOF; |
|
839 s->out++; |
|
840 offset--; |
|
841 if (s->last) s->z_err = Z_STREAM_END; |
|
842 } |
|
843 while (offset > 0) { |
|
844 int size = Z_BUFSIZE; |
|
845 if (offset < Z_BUFSIZE) size = (int)offset; |
|
846 |
|
847 size = gzread(file, s->outbuf, (uInt)size); |
|
848 if (size <= 0) return -1L; |
|
849 offset -= size; |
|
850 } |
|
851 return s->out; |
|
852 } |
|
853 |
|
854 /* =========================================================================== |
|
855 Rewinds input file. |
|
856 */ |
|
857 int ZEXPORT gzrewind (file) |
|
858 gzFile file; |
|
859 { |
|
860 gz_stream *s = (gz_stream*)file; |
|
861 |
|
862 if (s == NULL || s->mode != 'r') return -1; |
|
863 |
|
864 s->z_err = Z_OK; |
|
865 s->z_eof = 0; |
|
866 s->back = EOF; |
|
867 s->stream.avail_in = 0; |
|
868 s->stream.next_in = s->inbuf; |
|
869 s->crc = crc32(0L, Z_NULL, 0); |
|
870 if (!s->transparent) (void)inflateReset(&s->stream); |
|
871 s->in = 0; |
|
872 s->out = 0; |
|
873 return fseek(s->file, s->start, SEEK_SET); |
|
874 } |
|
875 |
|
876 /* =========================================================================== |
|
877 Returns the starting position for the next gzread or gzwrite on the |
|
878 given compressed file. This position represents a number of bytes in the |
|
879 uncompressed data stream. |
|
880 */ |
|
881 z_off_t ZEXPORT gztell (file) |
|
882 gzFile file; |
|
883 { |
|
884 return gzseek(file, 0L, SEEK_CUR); |
|
885 } |
|
886 |
|
887 /* =========================================================================== |
|
888 Returns 1 when EOF has previously been detected reading the given |
|
889 input stream, otherwise zero. |
|
890 */ |
|
891 int ZEXPORT gzeof (file) |
|
892 gzFile file; |
|
893 { |
|
894 gz_stream *s = (gz_stream*)file; |
|
895 |
|
896 /* With concatenated compressed files that can have embedded |
|
897 * crc trailers, z_eof is no longer the only/best indicator of EOF |
|
898 * on a gz_stream. Handle end-of-stream error explicitly here. |
|
899 */ |
|
900 if (s == NULL || s->mode != 'r') return 0; |
|
901 if (s->z_eof) return 1; |
|
902 return s->z_err == Z_STREAM_END; |
|
903 } |
|
904 |
|
905 /* =========================================================================== |
|
906 Returns 1 if reading and doing so transparently, otherwise zero. |
|
907 */ |
|
908 int ZEXPORT gzdirect (file) |
|
909 gzFile file; |
|
910 { |
|
911 gz_stream *s = (gz_stream*)file; |
|
912 |
|
913 if (s == NULL || s->mode != 'r') return 0; |
|
914 return s->transparent; |
|
915 } |
|
916 |
|
917 /* =========================================================================== |
|
918 Outputs a long in LSB order to the given file |
|
919 */ |
|
920 local void putLong (file, x) |
|
921 FILE *file; |
|
922 uLong x; |
|
923 { |
|
924 int n; |
|
925 for (n = 0; n < 4; n++) { |
|
926 fputc((int)(x & 0xff), file); |
|
927 x >>= 8; |
|
928 } |
|
929 } |
|
930 |
|
931 /* =========================================================================== |
|
932 Reads a long in LSB order from the given gz_stream. Sets z_err in case |
|
933 of error. |
|
934 */ |
|
935 local uLong getLong (s) |
|
936 gz_stream *s; |
|
937 { |
|
938 uLong x = (uLong)get_byte(s); |
|
939 int c; |
|
940 |
|
941 x += ((uLong)get_byte(s))<<8; |
|
942 x += ((uLong)get_byte(s))<<16; |
|
943 c = get_byte(s); |
|
944 if (c == EOF) s->z_err = Z_DATA_ERROR; |
|
945 x += ((uLong)c)<<24; |
|
946 return x; |
|
947 } |
|
948 |
|
949 /* =========================================================================== |
|
950 Flushes all pending output if necessary, closes the compressed file |
|
951 and deallocates all the (de)compression state. |
|
952 */ |
|
953 int ZEXPORT gzclose (file) |
|
954 gzFile file; |
|
955 { |
|
956 gz_stream *s = (gz_stream*)file; |
|
957 |
|
958 if (s == NULL) return Z_STREAM_ERROR; |
|
959 |
|
960 if (s->mode == 'w') { |
|
961 #ifdef NO_GZCOMPRESS |
|
962 return Z_STREAM_ERROR; |
|
963 #else |
|
964 if (do_flush (file, Z_FINISH) != Z_OK) |
|
965 return destroy((gz_stream*)file); |
|
966 |
|
967 putLong (s->file, s->crc); |
|
968 putLong (s->file, (uLong)(s->in & 0xffffffff)); |
|
969 #endif |
|
970 } |
|
971 return destroy((gz_stream*)file); |
|
972 } |
|
973 |
|
974 #ifdef STDC |
|
975 # define zstrerror(errnum) strerror(errnum) |
|
976 #else |
|
977 # define zstrerror(errnum) "" |
|
978 #endif |
|
979 |
|
980 /* =========================================================================== |
|
981 Returns the error message for the last error which occurred on the |
|
982 given compressed file. errnum is set to zlib error number. If an |
|
983 error occurred in the file system and not in the compression library, |
|
984 errnum is set to Z_ERRNO and the application may consult errno |
|
985 to get the exact error code. |
|
986 */ |
|
987 const char * ZEXPORT gzerror (file, errnum) |
|
988 gzFile file; |
|
989 int *errnum; |
|
990 { |
|
991 char *m; |
|
992 gz_stream *s = (gz_stream*)file; |
|
993 |
|
994 if (s == NULL) { |
|
995 *errnum = Z_STREAM_ERROR; |
|
996 return (const char*)ERR_MSG(Z_STREAM_ERROR); |
|
997 } |
|
998 *errnum = s->z_err; |
|
999 if (*errnum == Z_OK) return (const char*)""; |
|
1000 |
|
1001 m = (char*)(*errnum == Z_ERRNO ? zstrerror(errno) : s->stream.msg); |
|
1002 |
|
1003 if (m == NULL || *m == '\0') m = (char*)ERR_MSG(s->z_err); |
|
1004 |
|
1005 TRYFREE(s->msg); |
|
1006 s->msg = (char*)ALLOC(strlen(s->path) + strlen(m) + 3); |
|
1007 if (s->msg == Z_NULL) return (const char*)ERR_MSG(Z_MEM_ERROR); |
|
1008 strcpy(s->msg, s->path); |
|
1009 strcat(s->msg, ": "); |
|
1010 strcat(s->msg, m); |
|
1011 return (const char*)s->msg; |
|
1012 } |
|
1013 |
|
1014 /* =========================================================================== |
|
1015 Clear the error and end-of-file flags, and do the same for the real file. |
|
1016 */ |
|
1017 void ZEXPORT gzclearerr (file) |
|
1018 gzFile file; |
|
1019 { |
|
1020 gz_stream *s = (gz_stream*)file; |
|
1021 |
|
1022 if (s == NULL) return; |
|
1023 if (s->z_err != Z_STREAM_END) s->z_err = Z_OK; |
|
1024 s->z_eof = 0; |
|
1025 clearerr(s->file); |
|
1026 } |