1 /* vi: set sw=4 ts=4: */
3 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
7 #include "bb_archive.h"
9 void FAST_FUNC init_transformer_state(transformer_state_t *xstate)
11 memset(xstate, 0, sizeof(*xstate));
14 int FAST_FUNC check_signature16(transformer_state_t *xstate, unsigned magic16)
16 if (!xstate->signature_skipped) {
18 if (full_read(xstate->src_fd, &magic2, 2) != 2 || magic2 != magic16) {
19 bb_error_msg("invalid magic");
22 xstate->signature_skipped = 2;
27 ssize_t FAST_FUNC transformer_write(transformer_state_t *xstate, const void *buf, size_t bufsize)
31 if (xstate->mem_output_size_max != 0) {
32 size_t pos = xstate->mem_output_size;
35 size = (xstate->mem_output_size += bufsize);
36 if (size > xstate->mem_output_size_max) {
37 free(xstate->mem_output_buf);
38 xstate->mem_output_buf = NULL;
39 bb_perror_msg("buffer %u too small", (unsigned)xstate->mem_output_size_max);
43 xstate->mem_output_buf = xrealloc(xstate->mem_output_buf, size + 1);
44 memcpy(xstate->mem_output_buf + pos, buf, bufsize);
45 xstate->mem_output_buf[size] = '\0';
48 nwrote = full_write(xstate->dst_fd, buf, bufsize);
49 if (nwrote != (ssize_t)bufsize) {
50 bb_perror_msg("write");
59 ssize_t FAST_FUNC xtransformer_write(transformer_state_t *xstate, const void *buf, size_t bufsize)
61 ssize_t nwrote = transformer_write(xstate, buf, bufsize);
62 if (nwrote != (ssize_t)bufsize) {
68 void check_errors_in_children(int signo)
73 /* block waiting for any child */
74 if (wait(&status) < 0)
76 return; /* probably there are no children */
80 /* Wait for any child without blocking */
82 if (wait_any_nohang(&status) < 0)
84 /* wait failed?! I'm confused... */
87 /*if (WIFEXITED(status) && WEXITSTATUS(status) == 0)*/
88 /* On Linux, the above can be checked simply as: */
90 /* this child exited with 0 */
93 if (!WIFSIGNALED(status) && !WIFEXITED(status)) ???;
99 /* transformer(), more than meets the eye */
101 void FAST_FUNC fork_transformer(int fd,
102 int signature_skipped,
103 IF_DESKTOP(long long) int FAST_FUNC (*transformer)(transformer_state_t *xstate)
106 void FAST_FUNC fork_transformer(int fd, const char *transform_prog)
109 struct fd_pair fd_pipe;
112 xpiped_pair(fd_pipe);
113 pid = BB_MMU ? xfork() : xvfork();
116 close(fd_pipe.rd); /* we don't want to read from the parent */
117 // FIXME: error check?
120 IF_DESKTOP(long long) int r;
121 transformer_state_t xstate;
122 init_transformer_state(&xstate);
123 xstate.signature_skipped = signature_skipped;
125 xstate.dst_fd = fd_pipe.wr;
126 r = transformer(&xstate);
127 if (ENABLE_FEATURE_CLEAN_UP) {
128 close(fd_pipe.wr); /* send EOF */
131 /* must be _exit! bug was actually seen here */
132 _exit(/*error if:*/ r < 0);
138 xmove_fd(fd_pipe.wr, 1);
139 argv[0] = (char*)transform_prog;
140 argv[1] = (char*)"-cf";
141 argv[2] = (char*)"-";
143 BB_EXECVP(transform_prog, argv);
144 bb_perror_msg_and_die("can't execute '%s'", transform_prog);
151 close(fd_pipe.wr); /* don't want to write to the child */
152 xmove_fd(fd_pipe.rd, fd);
156 #if SEAMLESS_COMPRESSION
158 /* Used by e.g. rpm which gives us a fd without filename,
159 * thus we can't guess the format from filename's extension.
161 static transformer_state_t *setup_transformer_on_fd(int fd, int fail_if_not_compressed)
168 transformer_state_t *xstate;
170 xstate = xzalloc(sizeof(*xstate));
172 xstate->signature_skipped = 2;
174 /* .gz and .bz2 both have 2-byte signature, and their
175 * unpack_XXX_stream wants this header skipped. */
176 xread(fd, magic.b16, sizeof(magic.b16[0]));
177 if (ENABLE_FEATURE_SEAMLESS_GZ
178 && magic.b16[0] == GZIP_MAGIC
180 xstate->xformer = unpack_gz_stream;
181 USE_FOR_NOMMU(xstate->xformer_prog = "gunzip";)
184 if (ENABLE_FEATURE_SEAMLESS_Z
185 && magic.b16[0] == COMPRESS_MAGIC
187 xstate->xformer = unpack_Z_stream;
188 USE_FOR_NOMMU(xstate->xformer_prog = "uncompress";)
191 if (ENABLE_FEATURE_SEAMLESS_BZ2
192 && magic.b16[0] == BZIP2_MAGIC
194 xstate->xformer = unpack_bz2_stream;
195 USE_FOR_NOMMU(xstate->xformer_prog = "bunzip2";)
198 if (ENABLE_FEATURE_SEAMLESS_XZ
199 && magic.b16[0] == XZ_MAGIC1
201 xstate->signature_skipped = 6;
202 xread(fd, magic.b32, sizeof(magic.b32[0]));
203 if (magic.b32[0] == XZ_MAGIC2) {
204 xstate->xformer = unpack_xz_stream;
205 USE_FOR_NOMMU(xstate->xformer_prog = "unxz";)
210 /* No known magic seen */
211 if (fail_if_not_compressed)
212 bb_error_msg_and_die("no gzip"
213 IF_FEATURE_SEAMLESS_BZ2("/bzip2")
214 IF_FEATURE_SEAMLESS_XZ("/xz")
217 /* Some callers expect this function to "consume" fd
218 * even if data is not compressed. In this case,
219 * we return a state with trivial transformer.
221 // USE_FOR_MMU(xstate->xformer = copy_stream;)
222 // USE_FOR_NOMMU(xstate->xformer_prog = "cat";)
228 /* Used by e.g. rpm which gives us a fd without filename,
229 * thus we can't guess the format from filename's extension.
231 int FAST_FUNC setup_unzip_on_fd(int fd, int fail_if_not_compressed)
233 transformer_state_t *xstate = setup_transformer_on_fd(fd, fail_if_not_compressed);
235 if (!xstate || !xstate->xformer) {
241 fork_transformer_with_no_sig(xstate->src_fd, xstate->xformer);
243 /* NOMMU version of fork_transformer execs
244 * an external unzipper that wants
245 * file position at the start of the file.
247 xlseek(fd, - xstate->signature_skipped, SEEK_CUR);
248 xstate->signature_skipped = 0;
249 fork_transformer_with_sig(xstate->src_fd, xstate->xformer, xstate->xformer_prog);
255 static transformer_state_t *open_transformer(const char *fname, int fail_if_not_compressed)
257 transformer_state_t *xstate;
260 fd = open(fname, O_RDONLY);
264 if (ENABLE_FEATURE_SEAMLESS_LZMA) {
265 /* .lzma has no header/signature, can only detect it by extension */
266 char *sfx = strrchr(fname, '.');
267 if (sfx && strcmp(sfx+1, "lzma") == 0) {
268 xstate = xzalloc(sizeof(*xstate));
270 xstate->xformer = unpack_lzma_stream;
271 USE_FOR_NOMMU(xstate->xformer_prog = "unlzma";)
276 xstate = setup_transformer_on_fd(fd, fail_if_not_compressed);
281 int FAST_FUNC open_zipped(const char *fname, int fail_if_not_compressed)
284 transformer_state_t *xstate;
286 xstate = open_transformer(fname, fail_if_not_compressed);
292 if (xstate->xformer) {
293 fork_transformer_with_no_sig(fd, xstate->xformer);
295 /* the file is not compressed */
296 xlseek(fd, - xstate->signature_skipped, SEEK_CUR);
297 xstate->signature_skipped = 0;
300 /* NOMMU can't avoid the seek :( */
301 xlseek(fd, - xstate->signature_skipped, SEEK_CUR);
302 xstate->signature_skipped = 0;
303 if (xstate->xformer) {
304 fork_transformer_with_sig(fd, xstate->xformer, xstate->xformer_prog);
305 } /* else: the file is not compressed */
312 void* FAST_FUNC xmalloc_open_zipped_read_close(const char *fname, size_t *maxsz_p)
315 transformer_state_t *xstate;
318 xstate = open_transformer(fname, /*fail_if_not_compressed:*/ 0);
319 if (!xstate) /* file open error */
323 if (xstate->xformer) {
324 /* In-memory decompression */
325 xstate->mem_output_size_max = maxsz_p ? *maxsz_p : (size_t)(INT_MAX - 4095);
326 xstate->xformer(xstate);
327 if (xstate->mem_output_buf) {
328 image = xstate->mem_output_buf;
330 *maxsz_p = xstate->mem_output_size;
333 /* File is not compressed */
335 xlseek(xstate->src_fd, - xstate->signature_skipped, SEEK_CUR);
336 xstate->signature_skipped = 0;
337 image = xmalloc_read(xstate->src_fd, maxsz_p);
341 bb_perror_msg("read error from '%s'", fname);
342 close(xstate->src_fd);
346 /* This version forks a subprocess - much more expensive */
350 fd = open_zipped(fname, /*fail_if_not_compressed:*/ 0);
354 image = xmalloc_read(fd, maxsz_p);
356 bb_perror_msg("read error from '%s'", fname);
362 #endif /* SEAMLESS_COMPRESSION */