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Move from read_gz to the pipe()+fork() method.

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open_transformer(), common code for pipe+fork.
Function pointer for read() no longer needed.
Allow inflate to be initialised with a specified buffer size to avoid
over-reading.
Reset static variables in inflate_get_next_window to fix a bug where
only the first file in a .zip would be be extracted.
This commit is contained in:
Glenn L McGrath
2003-11-15 23:19:05 +00:00
parent 54ac057c00
commit 5699b8525e
16 changed files with 156 additions and 284 deletions
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140
archival/libunarchive/decompress_unzip.c
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@@ -103,7 +103,7 @@ static unsigned int gunzip_bb; /* bit buffer */
static unsigned char gunzip_bk; /* bits in bit buffer */
/* These control the size of the bytebuffer */
#define BYTEBUFFER_MAX 0x8000
static unsigned int bytebuffer_max = 0x8000;
static unsigned char *bytebuffer = NULL;
static unsigned int bytebuffer_offset = 0;
static unsigned int bytebuffer_size = 0;
@@ -144,21 +144,16 @@ static const unsigned char border[] = {
16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
};
static void fill_bytebuffer(void)
{
if (bytebuffer_offset >= bytebuffer_size) {
/* Leave the first 4 bytes empty so we can always unwind the bitbuffer
* to the front of the bytebuffer, leave 4 bytes free at end of tail
* so we can easily top up buffer in check_trailer_gzip() */
bytebuffer_size = 4 + bb_xread(gunzip_src_fd, &bytebuffer[4], BYTEBUFFER_MAX - 8);
bytebuffer_offset = 4;
}
}
static unsigned int fill_bitbuffer(unsigned int bitbuffer, unsigned int *current, const unsigned int required)
{
while (*current < required) {
fill_bytebuffer();
if (bytebuffer_offset >= bytebuffer_size) {
/* Leave the first 4 bytes empty so we can always unwind the bitbuffer
* to the front of the bytebuffer, leave 4 bytes free at end of tail
* so we can easily top up buffer in check_trailer_gzip() */
bytebuffer_size = 4 + bb_xread(gunzip_src_fd, &bytebuffer[4], bytebuffer_max - 8);
bytebuffer_offset = 4;
}
bitbuffer |= ((unsigned int) bytebuffer[bytebuffer_offset]) << *current;
bytebuffer_offset++;
*current += 8;
@@ -861,9 +856,9 @@ static void calculate_gunzip_crc(void)
static int inflate_get_next_window(void)
{
static int needAnotherBlock = 1;
static int method = -1; // Method == -1 for stored, -2 for codes
static int e = 0;
static int needAnotherBlock = 1;
gunzip_outbuf_count = 0;
@@ -873,6 +868,8 @@ static int inflate_get_next_window(void)
if (needAnotherBlock) {
if(e) {
calculate_gunzip_crc();
e = 0;
needAnotherBlock = 1;
return 0;
} // Last block
method = inflate_block(&e);
@@ -895,54 +892,25 @@ static int inflate_get_next_window(void)
/* Doesnt get here */
}
/*
* User functions
*
* read_gz, GZ_gzReadOpen, GZ_gzReadClose, inflate
*/
extern ssize_t read_gz(int fd, void *buf, size_t count)
/* Initialise bytebuffer, be carefull not to overfill the buffer */
extern void inflate_init(unsigned int bufsize)
{
static int morebytes = 0, finished = 0;
if (morebytes) {
int bytesRead = morebytes > count ? count : morebytes;
memcpy(buf, gunzip_window + (gunzip_outbuf_count - morebytes), bytesRead);
morebytes -= bytesRead;
return bytesRead;
} else if (finished) {
return 0;
} else if (count >= 0x8000) { // We can decompress direcly to the buffer, 32k at a time
// Could decompress to larger buffer, but it must be a power of 2, and calculating that is probably more expensive than the benefit
unsigned char *old_gunzip_window = gunzip_window; // Save old window
gunzip_window = buf;
if (inflate_get_next_window() == 0) finished = 1;
gunzip_window = old_gunzip_window; // Restore old window
return gunzip_outbuf_count;
} else { // Oh well, need to split up the gunzip_window
int bytesRead;
if (inflate_get_next_window() == 0) finished = 1;
morebytes = gunzip_outbuf_count;
bytesRead = morebytes > count ? count : morebytes;
memcpy(buf, gunzip_window, bytesRead);
morebytes -= bytesRead;
return bytesRead;
}
/* Set the bytebuffer size, default is same as gunzip_wsize */
bytebuffer_max = bufsize + 8;
bytebuffer_offset = 4;
bytebuffer_size = 0;
}
extern void GZ_gzReadOpen(int fd, void *unused, int nUnused)
extern int inflate_unzip(int in, int out)
{
ssize_t nwrote;
typedef void (*sig_type) (int);
/* Allocate all global buffers (for DYN_ALLOC option) */
gunzip_window = xmalloc(gunzip_wsize);
gunzip_outbuf_count = 0;
gunzip_bytes_out = 0;
gunzip_src_fd = fd;
/* Input buffer */
bytebuffer = xmalloc(BYTEBUFFER_MAX);
gunzip_src_fd = in;
/* initialize gunzip_window, bit buffer */
gunzip_bk = 0;
@@ -950,10 +918,20 @@ extern void GZ_gzReadOpen(int fd, void *unused, int nUnused)
/* Create the crc table */
make_gunzip_crc_table();
}
extern void GZ_gzReadClose(void)
{
/* Allocate space for buffer */
bytebuffer = xmalloc(bytebuffer_max);
while(1) {
int ret = inflate_get_next_window();
nwrote = bb_full_write(out, gunzip_window, gunzip_outbuf_count);
if (nwrote == -1) {
bb_perror_msg("write");
return -1;
}
if (ret == 0) break;
}
/* Cleanup */
free(gunzip_window);
free(gunzip_crc_table);
@@ -967,57 +945,20 @@ extern void GZ_gzReadClose(void)
gunzip_bb >>= 8;
gunzip_bk -= 8;
}
}
/*extern int inflate(int in, int out) // Useful for testing read_gz
{
char buf[8192];
ssize_t nread, nwrote;
GZ_gzReadOpen(in, 0, 0);
while(1) { // Robbed from bb_copyfd.c
nread = read_gz(in, buf, sizeof(buf));
if (nread == 0) break; // no data to write
else if (nread == -1) {
bb_perror_msg("read");
return -1;
}
nwrote = bb_full_write(out, buf, nread);
if (nwrote == -1) {
bb_perror_msg("write");
return -1;
}
}
GZ_gzReadClose();
return 0;
}*/
extern int inflate(int in, int out)
{
ssize_t nwrote;
GZ_gzReadOpen(in, 0, 0);
while(1) {
int ret = inflate_get_next_window();
nwrote = bb_full_write(out, gunzip_window, gunzip_outbuf_count);
if (nwrote == -1) {
bb_perror_msg("write");
return -1;
}
if (ret == 0) break;
}
GZ_gzReadClose();
return 0;
}
extern void check_trailer_gzip(int src_fd)
extern int inflate_gunzip(int in, int out)
{
unsigned int stored_crc = 0;
unsigned char count;
inflate_unzip(in, out);
/* top up the input buffer with the rest of the trailer */
count = bytebuffer_size - bytebuffer_offset;
if (count < 8) {
bb_xread_all(src_fd, &bytebuffer[bytebuffer_size], 8 - count);
bb_xread_all(in, &bytebuffer[bytebuffer_size], 8 - count);
bytebuffer_size += 8 - count;
}
for (count = 0; count != 4; count++) {
@@ -1027,14 +968,15 @@ extern void check_trailer_gzip(int src_fd)
/* Validate decompression - crc */
if (stored_crc != (gunzip_crc ^ 0xffffffffL)) {
bb_error_msg_and_die("crc error");
bb_error_msg("crc error");
}
/* Validate decompression - size */
if (gunzip_bytes_out !=
(bytebuffer[bytebuffer_offset] | (bytebuffer[bytebuffer_offset+1] << 8) |
(bytebuffer[bytebuffer_offset+2] << 16) | (bytebuffer[bytebuffer_offset+3] << 24))) {
bb_error_msg_and_die("Incorrect length, but crc is correct");
bb_error_msg("Incorrect length");
}
return 0;
}