make compressed help code NOMMU- and NOFORK-friendly -
no forking anymore, bunzip2 unpack routine now does all it in memory.
diff --git a/archival/libunarchive/decompress_bunzip2.c b/archival/libunarchive/decompress_bunzip2.c
index d4db40e..3f0b0f6 100644
--- a/archival/libunarchive/decompress_bunzip2.c
+++ b/archival/libunarchive/decompress_bunzip2.c
@@ -62,34 +62,31 @@
/* Structure holding all the housekeeping data, including IO buffers and
memory that persists between calls to bunzip */
-typedef struct {
+struct bunzip_data {
/* State for interrupting output loop */
-
int writeCopies, writePos, writeRunCountdown, writeCount, writeCurrent;
/* I/O tracking data (file handles, buffers, positions, etc.) */
-
int in_fd, out_fd, inbufCount, inbufPos /*, outbufPos*/;
unsigned char *inbuf /*,*outbuf*/;
unsigned inbufBitCount, inbufBits;
/* The CRC values stored in the block header and calculated from the data */
-
uint32_t headerCRC, totalCRC, writeCRC;
- uint32_t *crc32Table;
- /* Intermediate buffer and its size (in bytes) */
+ /* Intermediate buffer and its size (in bytes) */
unsigned *dbuf, dbufSize;
- /* These things are a bit too big to go on the stack */
+ /* For I/O error handling */
+ jmp_buf jmpbuf;
+ /* Big things go last (register-relative addressing can be larger for big offsets */
+ uint32_t crc32Table[256];
unsigned char selectors[32768]; /* nSelectors=15 bits */
struct group_data groups[MAX_GROUPS]; /* Huffman coding tables */
+};
+/* typedef struct bunzip_data bunzip_data; -- done in .h file */
- /* For I/O error handling */
-
- jmp_buf jmpbuf;
-} bunzip_data;
/* Return the next nnn bits of input. All reads from the compressed input
are done through this function. All reads are big endian */
@@ -106,6 +103,7 @@
/* If we need to read more data from file into byte buffer, do so */
if (bd->inbufPos == bd->inbufCount) {
+ /* if "no input fd" case: in_fd == -1, read fails, we jump */
bd->inbufCount = read(bd->in_fd, bd->inbuf, IOBUF_SIZE);
if (bd->inbufCount <= 0)
longjmp(bd->jmpbuf, RETVAL_UNEXPECTED_INPUT_EOF);
@@ -519,7 +517,7 @@
are ignored, data is written to out_fd and return is RETVAL_OK or error.
*/
-static int read_bunzip(bunzip_data *bd, char *outbuf, int len)
+int read_bunzip(bunzip_data *bd, char *outbuf, int len)
{
const unsigned *dbuf;
int pos, current, previous, gotcount;
@@ -627,11 +625,16 @@
goto decode_next_byte;
}
+
/* Allocate the structure, read file header. If in_fd==-1, inbuf must contain
a complete bunzip file (len bytes long). If in_fd!=-1, inbuf and len are
ignored, and data is read from file handle into temporary buffer. */
-static int start_bunzip(bunzip_data **bdp, int in_fd, unsigned char *inbuf,
+/* Because bunzip2 is used for help text unpacking, and because bb_show_usage()
+ should work for NOFORK applets too, we must be extremely careful to not leak
+ any allocations! */
+
+int start_bunzip(bunzip_data **bdp, int in_fd, const unsigned char *inbuf,
int len)
{
bunzip_data *bd;
@@ -653,14 +656,15 @@
bd->in_fd = in_fd;
if (-1 == in_fd) {
- bd->inbuf = inbuf;
+ /* in this case, bd->inbuf is read-only */
+ bd->inbuf = (void*)inbuf; /* cast away const-ness */
bd->inbufCount = len;
} else
bd->inbuf = (unsigned char *)(bd + 1);
/* Init the CRC32 table (big endian) */
- bd->crc32Table = crc32_filltable(1);
+ crc32_filltable(bd->crc32Table, 1);
/* Setup for I/O error handling via longjmp */
@@ -670,19 +674,30 @@
/* Ensure that file starts with "BZh['1'-'9']." */
i = get_bits(bd, 32);
- if (((unsigned)(i - BZh0 - 1)) >= 9) return RETVAL_NOT_BZIP_DATA;
+ if ((unsigned)(i - BZh0 - 1) >= 9) return RETVAL_NOT_BZIP_DATA;
/* Fourth byte (ascii '1'-'9'), indicates block size in units of 100k of
uncompressed data. Allocate intermediate buffer for block. */
bd->dbufSize = 100000 * (i - BZh0);
- bd->dbuf = xmalloc(bd->dbufSize * sizeof(int));
+ /* Cannot use xmalloc - may leak bd in NOFORK case! */
+ bd->dbuf = malloc_or_warn(bd->dbufSize * sizeof(int));
+ if (!bd->dbuf) {
+ free(bd);
+ xfunc_die();
+ }
return RETVAL_OK;
}
-/* Example usage: decompress src_fd to dst_fd. (Stops at end of bzip data,
- not end of file.) */
+void dealloc_bunzip(bunzip_data *bd)
+{
+ free(bd->dbuf);
+ free(bd);
+}
+
+
+/* Decompress src_fd to dst_fd. Stops at end of bzip data, not end of file. */
USE_DESKTOP(long long) int
uncompressStream(int src_fd, int dst_fd)
@@ -693,7 +708,7 @@
int i;
outbuf = xmalloc(IOBUF_SIZE);
- i = start_bunzip(&bd, src_fd, 0, 0);
+ i = start_bunzip(&bd, src_fd, NULL, 0);
if (!i) {
for (;;) {
i = read_bunzip(bd, outbuf, IOBUF_SIZE);
@@ -719,8 +734,7 @@
} else {
bb_error_msg("decompression failed");
}
- free(bd->dbuf);
- free(bd);
+ dealloc_bunzip(bd);
free(outbuf);
return i ? i : USE_DESKTOP(total_written) + 0;