/* gzlib.c -- zlib functions common to reading and writing gzip files
- * Copyright (C) 2004, 2010 Mark Adler
+ * Copyright (C) 2004, 2010, 2011 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "gzguts.h"
+#if defined(_WIN32) && !defined(__BORLANDC__)
+# define LSEEK _lseeki64
+#else
#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
# define LSEEK lseek64
#else
# define LSEEK lseek
#endif
+#endif
/* Local functions */
local void gz_reset OF((gz_statep));
local void gz_reset(state)
gz_statep state;
{
+ state->x.have = 0; /* no output data available */
if (state->mode == GZ_READ) { /* for reading ... */
- state->have = 0; /* no output data available */
state->eof = 0; /* not at end of file */
+ state->past = 0; /* have not read past end yet */
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->x.pos = 0; /* no uncompressed data yet */
state->strm.avail_in = 0; /* no input data yet */
}
{
gz_statep state;
+ /* check input */
+ if (path == NULL)
+ return NULL;
+
/* allocate gzFile structure to return */
state = malloc(sizeof(gz_state));
if (state == NULL)
state->mode = GZ_NONE;
state->level = Z_DEFAULT_COMPRESSION;
state->strategy = Z_DEFAULT_STRATEGY;
+ state->direct = 0;
while (*mode) {
if (*mode >= '0' && *mode <= '9')
state->level = *mode - '0';
break;
case 'F':
state->strategy = Z_FIXED;
+ case 'T':
+ state->direct = 1;
default: /* could consider as an error, but just ignore */
;
}
return NULL;
}
+ /* can't force transparent read */
+ if (state->mode == GZ_READ) {
+ if (state->direct) {
+ free(state);
+ return NULL;
+ }
+ state->direct = 1; /* for empty file */
+ }
+
/* save the path name for error messages */
state->path = malloc(strlen(path) + 1);
if (state->path == NULL) {
return -1;
/* check and set requested size */
- if (size == 0)
- return -1;
+ if (size < 2)
+ size = 2; /* need two bytes to check magic header */
state->want = size;
return 0;
}
state = (gz_statep)file;
/* check that we're reading and that there's no error */
- if (state->mode != GZ_READ || state->err != Z_OK)
+ if (state->mode != GZ_READ ||
+ (state->err != Z_OK && state->err != Z_BUF_ERROR))
return -1;
/* back up and start over */
return -1;
/* check that there's no error */
- if (state->err != Z_OK)
+ if (state->err != Z_OK && state->err != Z_BUF_ERROR)
return -1;
/* can only seek from start or relative to current position */
/* normalize offset to a SEEK_CUR specification */
if (whence == SEEK_SET)
- offset -= state->pos;
+ offset -= state->x.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);
+ state->x.pos + offset >= 0) {
+ ret = LSEEK(state->fd, offset - state->x.have, SEEK_CUR);
if (ret == -1)
return -1;
- state->have = 0;
+ state->x.have = 0;
state->eof = 0;
+ state->past = 0;
state->seek = 0;
gz_error(state, Z_OK, NULL);
state->strm.avail_in = 0;
- state->pos += offset;
- return state->pos;
+ state->x.pos += offset;
+ return state->x.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;
+ offset += state->x.pos;
if (offset < 0) /* before start of file! */
return -1;
if (gzrewind(file) == -1) /* rewind, then skip to offset */
/* 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;
+ n = GT_OFF(state->x.have) || (z_off64_t)state->x.have > offset ?
+ (unsigned)offset : state->x.have;
+ state->x.have -= n;
+ state->x.next += n;
+ state->x.pos += n;
offset -= n;
}
state->seek = 1;
state->skip = offset;
}
- return state->pos + offset;
+ return state->x.pos + offset;
}
/* -- see zlib.h -- */
return -1;
/* return position */
- return state->pos + (state->seek ? state->skip : 0);
+ return state->x.pos + (state->seek ? state->skip : 0);
}
/* -- see zlib.h -- */
return 0;
/* return end-of-file state */
- return state->mode == GZ_READ ?
- (state->eof && state->strm.avail_in == 0 && state->have == 0) : 0;
+ return state->mode == GZ_READ ? state->past : 0;
}
/* -- see zlib.h -- */
return;
/* clear error and end-of-file */
- if (state->mode == GZ_READ)
+ if (state->mode == GZ_READ) {
state->eof = 0;
+ state->past = 0;
+ }
gz_error(state, Z_OK, NULL);
}
state->msg = NULL;
}
+ /* if fatal, set state->x.have to 0 so that the gzgetc() macro fails */
+ if (err != Z_OK && err != Z_BUF_ERROR)
+ state->x.have = 0;
+
/* set error code, and if no message, then done */
state->err = err;
if (msg == NULL)