contrib/libarchive-2.1/libarchive/archive_read_support_compression_program.c

   1 /*-
   2  * Copyright (c) 2007 Joerg Sonnenberger
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "archive_platform.h"
  27 __FBSDID("$FreeBSD$");
  28
  29 #ifdef HAVE_SYS_WAIT_H
  30 #  include <sys/wait.h>
  31 #endif
  32 #ifdef HAVE_ERRNO_H
  33 #  include <errno.h>
  34 #endif
  35 #ifdef HAVE_FCNTL_H
  36 #  include <fcntl.h>
  37 #endif
  38 #ifdef HAVE_LIMITS_H
  39 #  include <limits.h>
  40 #endif
  41 #ifdef HAVE_STDLIB_H
  42 #  include <stdlib.h>
  43 #endif
  44 #ifdef HAVE_STRING_H
  45 #  include <string.h>
  46 #endif
  47 #ifdef HAVE_UNISTD_H
  48 #  include <unistd.h>
  49 #endif
  50
  51 #include "archive.h"
  52 #include "archive_private.h"
  53 #include "archive_read_private.h"
  54
  55 #include "filter_fork.h"
  56
  57 struct archive_decompress_program {
  58         char            *description;
  59         pid_t            child;
  60         int              child_stdin, child_stdout;
  61
  62         char            *child_out_buf;
  63         char            *child_out_buf_next;
  64         size_t           child_out_buf_len, child_out_buf_avail;
  65
  66         const char      *child_in_buf;
  67         size_t           child_in_buf_avail;
  68 };
  69
  70 static int      archive_decompressor_program_bid(const void *, size_t);
  71 static int      archive_decompressor_program_finish(struct archive_read *);
  72 static int      archive_decompressor_program_init(struct archive_read *,
  73                     const void *, size_t);
  74 static ssize_t  archive_decompressor_program_read_ahead(struct archive_read *,
  75                     const void **, size_t);
  76 static ssize_t  archive_decompressor_program_read_consume(struct archive_read *,
  77                     size_t);
  78
  79 int
  80 archive_read_support_compression_program(struct archive *_a, const char *cmd)
  81 {
  82         struct archive_read *a = (struct archive_read *)_a;
  83         struct decompressor_t *decompressor;
  84
  85         if (cmd == NULL || *cmd == '\0')
  86                 return (ARCHIVE_WARN);
  87
  88         decompressor = __archive_read_register_compression(a,
  89                     archive_decompressor_program_bid,
  90                     archive_decompressor_program_init);
  91         if (decompressor == NULL)
  92                 return (ARCHIVE_WARN);
  93
  94         decompressor->config = strdup(cmd);
  95         return (ARCHIVE_OK);
  96 }
  97
  98 /*
  99  * If the user used us to register, they must really want us to
 100  * handle it, so this module always bids INT_MAX.
 101  */
 102 static int
 103 archive_decompressor_program_bid(const void *buff, size_t len)
 104 {
 105         (void)buff; /* UNUSED */
 106         (void)len; /* UNUSED */
 107
 108         return (INT_MAX); /* Default: We'll take it. */
 109 }
 110
 111 static ssize_t
 112 child_read(struct archive_read *a, char *buf, size_t buf_len)
 113 {
 114         struct archive_decompress_program *state = a->decompressor->data;
 115         ssize_t ret, requested;
 116
 117         if (state->child_stdout == -1)
 118                 return (-1);
 119
 120         if (buf_len == 0)
 121                 return (-1);
 122
 123 restart_read:
 124         requested = buf_len > SSIZE_MAX ? SSIZE_MAX : buf_len;
 125
 126         do {
 127                 ret = read(state->child_stdout, buf, requested);
 128         } while (ret == -1 && errno == EINTR);
 129
 130         if (ret > 0)
 131                 return (ret);
 132         if (ret == 0 || (ret == -1 && errno == EPIPE)) {
 133                 close(state->child_stdout);
 134                 state->child_stdout = -1;
 135                 return (0);
 136         }
 137         if (ret == -1 && errno != EAGAIN)
 138                 return (-1);
 139
 140         if (state->child_in_buf_avail == 0) {
 141                 ret = (a->client_reader)(&a->archive,
 142                     a->client_data, (const void **)&state->child_in_buf);
 143
 144                 if (ret < 0) {
 145                         close(state->child_stdin);
 146                         state->child_stdin = -1;
 147                         fcntl(state->child_stdout, F_SETFL, 0);
 148                         return (-1);
 149                 }
 150                 if (ret == 0) {
 151                         close(state->child_stdin);
 152                         state->child_stdin = -1;
 153                         fcntl(state->child_stdout, F_SETFL, 0);
 154                         goto restart_read;
 155                 }
 156                 state->child_in_buf_avail = ret;
 157         }
 158
 159         do {
 160                 ret = write(state->child_stdin, state->child_in_buf,
 161                     state->child_in_buf_avail);
 162         } while (ret == -1 && errno == EINTR);
 163
 164         if (ret > 0) {
 165                 state->child_in_buf += ret;
 166                 state->child_in_buf_avail -= ret;
 167                 goto restart_read;
 168         } else if (ret == -1 && errno == EAGAIN) {
 169                 __archive_check_child(state->child_stdin, state->child_stdout);
 170                 goto restart_read;
 171         } else if (ret == 0 || (ret == -1 && errno == EPIPE)) {
 172                 close(state->child_stdin);
 173                 state->child_stdout = -1;
 174                 fcntl(state->child_stdout, F_SETFL, 0);
 175                 goto restart_read;
 176         } else {
 177                 close(state->child_stdin);
 178                 state->child_stdin = -1;
 179                 fcntl(state->child_stdout, F_SETFL, 0);
 180                 return (-1);
 181         }
 182 }
 183
 184 static int
 185 archive_decompressor_program_init(struct archive_read *a, const void *buff, size_t n)
 186 {
 187         struct archive_decompress_program       *state;
 188         const char *cmd = a->decompressor->config;
 189         const char *prefix = "Program: ";
 190
 191
 192         state = (struct archive_decompress_program *)malloc(sizeof(*state));
 193         if (!state) {
 194                 archive_set_error(&a->archive, ENOMEM,
 195                     "Can't allocate input data");
 196                 return (ARCHIVE_FATAL);
 197         }
 198
 199         a->archive.compression_code = ARCHIVE_COMPRESSION_PROGRAM;
 200         state->description = (char *)malloc(strlen(prefix) + strlen(cmd) + 1);
 201         strcpy(state->description, prefix);
 202         strcat(state->description, cmd);
 203         a->archive.compression_name = state->description;
 204
 205         state->child_out_buf_next = state->child_out_buf = malloc(65536);
 206         if (!state->child_out_buf) {
 207                 free(state);
 208                 archive_set_error(&a->archive, ENOMEM,
 209                     "Can't allocate filter buffer");
 210                 return (ARCHIVE_FATAL);
 211         }
 212         state->child_out_buf_len = 65536;
 213         state->child_out_buf_avail = 0;
 214
 215         state->child_in_buf = buff;
 216         state->child_in_buf_avail = n;
 217
 218         if ((state->child = __archive_create_child(cmd,
 219                  &state->child_stdin, &state->child_stdout)) == -1) {
 220                 free(state->child_out_buf);
 221                 free(state);
 222                 archive_set_error(&a->archive, EINVAL,
 223                     "Can't initialise filter");
 224                 return (ARCHIVE_FATAL);
 225         }
 226
 227         a->decompressor->data = state;
 228         a->decompressor->read_ahead = archive_decompressor_program_read_ahead;
 229         a->decompressor->consume = archive_decompressor_program_read_consume;
 230         a->decompressor->skip = NULL;
 231         a->decompressor->finish = archive_decompressor_program_finish;
 232
 233         /* XXX Check that we can read at least one byte? */
 234         return (ARCHIVE_OK);
 235 }
 236
 237 static ssize_t
 238 archive_decompressor_program_read_ahead(struct archive_read *a, const void **buff,
 239     size_t min)
 240 {
 241         struct archive_decompress_program *state;
 242         ssize_t bytes_read;
 243
 244         state = (struct archive_decompress_program *)a->decompressor->data;
 245
 246         if (min > state->child_out_buf_len)
 247                 min = state->child_out_buf_len;
 248
 249         while (state->child_stdout != -1 && min > state->child_out_buf_avail) {
 250                 if (state->child_out_buf != state->child_out_buf_next) {
 251                         memmove(state->child_out_buf, state->child_out_buf_next,
 252                             state->child_out_buf_avail);
 253                         state->child_out_buf_next = state->child_out_buf;
 254                 }
 255
 256                 bytes_read = child_read(a,
 257                     state->child_out_buf + state->child_out_buf_avail,
 258                     state->child_out_buf_len - state->child_out_buf_avail);
 259                 if (bytes_read == -1)
 260                         return (-1);
 261                 if (bytes_read == 0)
 262                         break;
 263                 state->child_out_buf_avail += bytes_read;
 264                 a->archive.raw_position += bytes_read;
 265         }
 266
 267         *buff = state->child_out_buf_next;
 268         return (state->child_out_buf_avail);
 269 }
 270
 271 static ssize_t
 272 archive_decompressor_program_read_consume(struct archive_read *a, size_t request)
 273 {
 274         struct archive_decompress_program *state;
 275
 276         state = (struct archive_decompress_program *)a->decompressor->data;
 277
 278         state->child_out_buf_next += request;
 279         state->child_out_buf_avail -= request;
 280
 281         a->archive.file_position += request;
 282         return (request);
 283 }
 284
 285 static int
 286 archive_decompressor_program_finish(struct archive_read *a)
 287 {
 288         struct archive_decompress_program       *state;
 289         int status;
 290
 291         state = (struct archive_decompress_program *)a->decompressor->data;
 292
 293         /* Release our configuration data. */
 294         free(a->decompressor->config);
 295         a->decompressor->config = NULL;
 296
 297         /* Shut down the child. */
 298         if (state->child_stdin != -1)
 299                 close(state->child_stdin);
 300         if (state->child_stdout != -1)
 301                 close(state->child_stdout);
 302         while (waitpid(state->child, &status, 0) == -1 && errno == EINTR)
 303                 continue;
 304
 305         /* Release our private data. */
 306         free(state->child_out_buf);
 307         free(state->description);
 308         free(state);
 309         a->decompressor->data = NULL;
 310
 311         return (ARCHIVE_OK);
 312 }