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-rw-r--r--Modules/zlib/gzlib.c537
1 files changed, 537 insertions, 0 deletions
diff --git a/Modules/zlib/gzlib.c b/Modules/zlib/gzlib.c
new file mode 100644
index 0000000..603e60e
--- /dev/null
+++ b/Modules/zlib/gzlib.c
@@ -0,0 +1,537 @@
+/* gzlib.c -- zlib functions common to reading and writing gzip files
+ * Copyright (C) 2004, 2010 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include "gzguts.h"
+
+#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
+# define LSEEK lseek64
+#else
+# define LSEEK lseek
+#endif
+
+/* Local functions */
+local void gz_reset OF((gz_statep));
+local gzFile gz_open OF((const char *, int, const char *));
+
+#if defined UNDER_CE
+
+/* Map the Windows error number in ERROR to a locale-dependent error message
+ string and return a pointer to it. Typically, the values for ERROR come
+ from GetLastError.
+
+ The string pointed to shall not be modified by the application, but may be
+ overwritten by a subsequent call to gz_strwinerror
+
+ The gz_strwinerror function does not change the current setting of
+ GetLastError. */
+char ZLIB_INTERNAL *gz_strwinerror (error)
+ DWORD error;
+{
+ static char buf[1024];
+
+ wchar_t *msgbuf;
+ DWORD lasterr = GetLastError();
+ DWORD chars = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM
+ | FORMAT_MESSAGE_ALLOCATE_BUFFER,
+ NULL,
+ error,
+ 0, /* Default language */
+ (LPVOID)&msgbuf,
+ 0,
+ NULL);
+ if (chars != 0) {
+ /* If there is an \r\n appended, zap it. */
+ if (chars >= 2
+ && msgbuf[chars - 2] == '\r' && msgbuf[chars - 1] == '\n') {
+ chars -= 2;
+ msgbuf[chars] = 0;
+ }
+
+ if (chars > sizeof (buf) - 1) {
+ chars = sizeof (buf) - 1;
+ msgbuf[chars] = 0;
+ }
+
+ wcstombs(buf, msgbuf, chars + 1);
+ LocalFree(msgbuf);
+ }
+ else {
+ sprintf(buf, "unknown win32 error (%ld)", error);
+ }
+
+ SetLastError(lasterr);
+ return buf;
+}
+
+#endif /* UNDER_CE */
+
+/* Reset gzip file state */
+local void gz_reset(state)
+ gz_statep state;
+{
+ if (state->mode == GZ_READ) { /* for reading ... */
+ state->have = 0; /* no output data available */
+ state->eof = 0; /* not at end of file */
+ state->how = LOOK; /* look for gzip header */
+ state->direct = 1; /* default for empty file */
+ }
+ state->seek = 0; /* no seek request pending */
+ gz_error(state, Z_OK, NULL); /* clear error */
+ state->pos = 0; /* no uncompressed data yet */
+ state->strm.avail_in = 0; /* no input data yet */
+}
+
+/* Open a gzip file either by name or file descriptor. */
+local gzFile gz_open(path, fd, mode)
+ const char *path;
+ int fd;
+ const char *mode;
+{
+ gz_statep state;
+
+ /* allocate gzFile structure to return */
+ state = malloc(sizeof(gz_state));
+ if (state == NULL)
+ return NULL;
+ state->size = 0; /* no buffers allocated yet */
+ state->want = GZBUFSIZE; /* requested buffer size */
+ state->msg = NULL; /* no error message yet */
+
+ /* interpret mode */
+ state->mode = GZ_NONE;
+ state->level = Z_DEFAULT_COMPRESSION;
+ state->strategy = Z_DEFAULT_STRATEGY;
+ while (*mode) {
+ if (*mode >= '0' && *mode <= '9')
+ state->level = *mode - '0';
+ else
+ switch (*mode) {
+ case 'r':
+ state->mode = GZ_READ;
+ break;
+#ifndef NO_GZCOMPRESS
+ case 'w':
+ state->mode = GZ_WRITE;
+ break;
+ case 'a':
+ state->mode = GZ_APPEND;
+ break;
+#endif
+ case '+': /* can't read and write at the same time */
+ free(state);
+ return NULL;
+ case 'b': /* ignore -- will request binary anyway */
+ break;
+ case 'f':
+ state->strategy = Z_FILTERED;
+ break;
+ case 'h':
+ state->strategy = Z_HUFFMAN_ONLY;
+ break;
+ case 'R':
+ state->strategy = Z_RLE;
+ break;
+ case 'F':
+ state->strategy = Z_FIXED;
+ default: /* could consider as an error, but just ignore */
+ ;
+ }
+ mode++;
+ }
+
+ /* must provide an "r", "w", or "a" */
+ if (state->mode == GZ_NONE) {
+ free(state);
+ return NULL;
+ }
+
+ /* save the path name for error messages */
+ state->path = malloc(strlen(path) + 1);
+ if (state->path == NULL) {
+ free(state);
+ return NULL;
+ }
+ strcpy(state->path, path);
+
+ /* open the file with the appropriate mode (or just use fd) */
+ state->fd = fd != -1 ? fd :
+ open(path,
+#ifdef O_LARGEFILE
+ O_LARGEFILE |
+#endif
+#ifdef O_BINARY
+ O_BINARY |
+#endif
+ (state->mode == GZ_READ ?
+ O_RDONLY :
+ (O_WRONLY | O_CREAT | (
+ state->mode == GZ_WRITE ?
+ O_TRUNC :
+ O_APPEND))),
+ 0666);
+ if (state->fd == -1) {
+ free(state->path);
+ free(state);
+ return NULL;
+ }
+ if (state->mode == GZ_APPEND)
+ state->mode = GZ_WRITE; /* simplify later checks */
+
+ /* save the current position for rewinding (only if reading) */
+ if (state->mode == GZ_READ) {
+ state->start = LSEEK(state->fd, 0, SEEK_CUR);
+ if (state->start == -1) state->start = 0;
+ }
+
+ /* initialize stream */
+ gz_reset(state);
+
+ /* return stream */
+ return (gzFile)state;
+}
+
+/* -- see zlib.h -- */
+gzFile ZEXPORT gzopen(path, mode)
+ const char *path;
+ const char *mode;
+{
+ return gz_open(path, -1, mode);
+}
+
+/* -- see zlib.h -- */
+gzFile ZEXPORT gzopen64(path, mode)
+ const char *path;
+ const char *mode;
+{
+ return gz_open(path, -1, mode);
+}
+
+/* -- see zlib.h -- */
+gzFile ZEXPORT gzdopen(fd, mode)
+ int fd;
+ const char *mode;
+{
+ char *path; /* identifier for error messages */
+ gzFile gz;
+
+ if (fd == -1 || (path = malloc(7 + 3 * sizeof(int))) == NULL)
+ return NULL;
+ sprintf(path, "<fd:%d>", fd); /* for debugging */
+ gz = gz_open(path, fd, mode);
+ free(path);
+ return gz;
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzbuffer(file, size)
+ gzFile file;
+ unsigned size;
+{
+ gz_statep state;
+
+ /* get internal structure and check integrity */
+ if (file == NULL)
+ return -1;
+ state = (gz_statep)file;
+ if (state->mode != GZ_READ && state->mode != GZ_WRITE)
+ return -1;
+
+ /* make sure we haven't already allocated memory */
+ if (state->size != 0)
+ return -1;
+
+ /* check and set requested size */
+ if (size == 0)
+ return -1;
+ state->want = size;
+ return 0;
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzrewind(file)
+ gzFile file;
+{
+ gz_statep state;
+
+ /* get internal structure */
+ if (file == NULL)
+ return -1;
+ state = (gz_statep)file;
+
+ /* check that we're reading and that there's no error */
+ if (state->mode != GZ_READ || state->err != Z_OK)
+ return -1;
+
+ /* back up and start over */
+ if (LSEEK(state->fd, state->start, SEEK_SET) == -1)
+ return -1;
+ gz_reset(state);
+ return 0;
+}
+
+/* -- see zlib.h -- */
+z_off64_t ZEXPORT gzseek64(file, offset, whence)
+ gzFile file;
+ z_off64_t offset;
+ int whence;
+{
+ unsigned n;
+ z_off64_t ret;
+ gz_statep state;
+
+ /* get internal structure and check integrity */
+ if (file == NULL)
+ return -1;
+ state = (gz_statep)file;
+ if (state->mode != GZ_READ && state->mode != GZ_WRITE)
+ return -1;
+
+ /* check that there's no error */
+ if (state->err != Z_OK)
+ return -1;
+
+ /* can only seek from start or relative to current position */
+ if (whence != SEEK_SET && whence != SEEK_CUR)
+ return -1;
+
+ /* normalize offset to a SEEK_CUR specification */
+ if (whence == SEEK_SET)
+ offset -= state->pos;
+ else if (state->seek)
+ offset += state->skip;
+ state->seek = 0;
+
+ /* if within raw area while reading, just go there */
+ if (state->mode == GZ_READ && state->how == COPY &&
+ state->pos + offset >= state->raw) {
+ ret = LSEEK(state->fd, offset - state->have, SEEK_CUR);
+ if (ret == -1)
+ return -1;
+ state->have = 0;
+ state->eof = 0;
+ state->seek = 0;
+ gz_error(state, Z_OK, NULL);
+ state->strm.avail_in = 0;
+ state->pos += offset;
+ return state->pos;
+ }
+
+ /* calculate skip amount, rewinding if needed for back seek when reading */
+ if (offset < 0) {
+ if (state->mode != GZ_READ) /* writing -- can't go backwards */
+ return -1;
+ offset += state->pos;
+ if (offset < 0) /* before start of file! */
+ return -1;
+ if (gzrewind(file) == -1) /* rewind, then skip to offset */
+ return -1;
+ }
+
+ /* if reading, skip what's in output buffer (one less gzgetc() check) */
+ if (state->mode == GZ_READ) {
+ n = GT_OFF(state->have) || (z_off64_t)state->have > offset ?
+ (unsigned)offset : state->have;
+ state->have -= n;
+ state->next += n;
+ state->pos += n;
+ offset -= n;
+ }
+
+ /* request skip (if not zero) */
+ if (offset) {
+ state->seek = 1;
+ state->skip = offset;
+ }
+ return state->pos + offset;
+}
+
+/* -- see zlib.h -- */
+z_off_t ZEXPORT gzseek(file, offset, whence)
+ gzFile file;
+ z_off_t offset;
+ int whence;
+{
+ z_off64_t ret;
+
+ ret = gzseek64(file, (z_off64_t)offset, whence);
+ return ret == (z_off_t)ret ? (z_off_t)ret : -1;
+}
+
+/* -- see zlib.h -- */
+z_off64_t ZEXPORT gztell64(file)
+ gzFile file;
+{
+ gz_statep state;
+
+ /* get internal structure and check integrity */
+ if (file == NULL)
+ return -1;
+ state = (gz_statep)file;
+ if (state->mode != GZ_READ && state->mode != GZ_WRITE)
+ return -1;
+
+ /* return position */
+ return state->pos + (state->seek ? state->skip : 0);
+}
+
+/* -- see zlib.h -- */
+z_off_t ZEXPORT gztell(file)
+ gzFile file;
+{
+ z_off64_t ret;
+
+ ret = gztell64(file);
+ return ret == (z_off_t)ret ? (z_off_t)ret : -1;
+}
+
+/* -- see zlib.h -- */
+z_off64_t ZEXPORT gzoffset64(file)
+ gzFile file;
+{
+ z_off64_t offset;
+ gz_statep state;
+
+ /* get internal structure and check integrity */
+ if (file == NULL)
+ return -1;
+ state = (gz_statep)file;
+ if (state->mode != GZ_READ && state->mode != GZ_WRITE)
+ return -1;
+
+ /* compute and return effective offset in file */
+ offset = LSEEK(state->fd, 0, SEEK_CUR);
+ if (offset == -1)
+ return -1;
+ if (state->mode == GZ_READ) /* reading */
+ offset -= state->strm.avail_in; /* don't count buffered input */
+ return offset;
+}
+
+/* -- see zlib.h -- */
+z_off_t ZEXPORT gzoffset(file)
+ gzFile file;
+{
+ z_off64_t ret;
+
+ ret = gzoffset64(file);
+ return ret == (z_off_t)ret ? (z_off_t)ret : -1;
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzeof(file)
+ gzFile file;
+{
+ gz_statep state;
+
+ /* get internal structure and check integrity */
+ if (file == NULL)
+ return 0;
+ state = (gz_statep)file;
+ if (state->mode != GZ_READ && state->mode != GZ_WRITE)
+ return 0;
+
+ /* return end-of-file state */
+ return state->mode == GZ_READ ?
+ (state->eof && state->strm.avail_in == 0 && state->have == 0) : 0;
+}
+
+/* -- see zlib.h -- */
+const char * ZEXPORT gzerror(file, errnum)
+ gzFile file;
+ int *errnum;
+{
+ gz_statep state;
+
+ /* get internal structure and check integrity */
+ if (file == NULL)
+ return NULL;
+ state = (gz_statep)file;
+ if (state->mode != GZ_READ && state->mode != GZ_WRITE)
+ return NULL;
+
+ /* return error information */
+ if (errnum != NULL)
+ *errnum = state->err;
+ return state->msg == NULL ? "" : state->msg;
+}
+
+/* -- see zlib.h -- */
+void ZEXPORT gzclearerr(file)
+ gzFile file;
+{
+ gz_statep state;
+
+ /* get internal structure and check integrity */
+ if (file == NULL)
+ return;
+ state = (gz_statep)file;
+ if (state->mode != GZ_READ && state->mode != GZ_WRITE)
+ return;
+
+ /* clear error and end-of-file */
+ if (state->mode == GZ_READ)
+ state->eof = 0;
+ gz_error(state, Z_OK, NULL);
+}
+
+/* Create an error message in allocated memory and set state->err and
+ state->msg accordingly. Free any previous error message already there. Do
+ not try to free or allocate space if the error is Z_MEM_ERROR (out of
+ memory). Simply save the error message as a static string. If there is an
+ allocation failure constructing the error message, then convert the error to
+ out of memory. */
+void ZLIB_INTERNAL gz_error(state, err, msg)
+ gz_statep state;
+ int err;
+ const char *msg;
+{
+ /* free previously allocated message and clear */
+ if (state->msg != NULL) {
+ if (state->err != Z_MEM_ERROR)
+ free(state->msg);
+ state->msg = NULL;
+ }
+
+ /* set error code, and if no message, then done */
+ state->err = err;
+ if (msg == NULL)
+ return;
+
+ /* for an out of memory error, save as static string */
+ if (err == Z_MEM_ERROR) {
+ state->msg = (char *)msg;
+ return;
+ }
+
+ /* construct error message with path */
+ if ((state->msg = malloc(strlen(state->path) + strlen(msg) + 3)) == NULL) {
+ state->err = Z_MEM_ERROR;
+ state->msg = (char *)"out of memory";
+ return;
+ }
+ strcpy(state->msg, state->path);
+ strcat(state->msg, ": ");
+ strcat(state->msg, msg);
+ return;
+}
+
+#ifndef INT_MAX
+/* portably return maximum value for an int (when limits.h presumed not
+ available) -- we need to do this to cover cases where 2's complement not
+ used, since C standard permits 1's complement and sign-bit representations,
+ otherwise we could just use ((unsigned)-1) >> 1 */
+unsigned ZLIB_INTERNAL gz_intmax()
+{
+ unsigned p, q;
+
+ p = 1;
+ do {
+ q = p;
+ p <<= 1;
+ p++;
+ } while (p > q);
+ return q >> 1;
+}
+#endif
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