aboutsummaryrefslogtreecommitdiff
path: root/lib/bunzip.c
diff options
context:
space:
mode:
authorRob Landley <rob@landley.net>2007-01-18 22:00:12 -0500
committerRob Landley <rob@landley.net>2007-01-18 22:00:12 -0500
commit6000f13e8ac8c17c1f01fcafc8066bb7b419f224 (patch)
tree5620ab49b2bdf8fd8189840067fdfd2020e4ba58 /lib/bunzip.c
parent901637760b4206e968e73dd5ff7430c107c27b57 (diff)
downloadtoybox-6000f13e8ac8c17c1f01fcafc8066bb7b419f224.tar.gz
In bunzip replace setjmp/longjmp handling with error_exit(), replace string
based handling of a 6-byte header with with two 24-bit integer reads. Use xmalloc() and xzalloc().
Diffstat (limited to 'lib/bunzip.c')
-rw-r--r--lib/bunzip.c49
1 files changed, 15 insertions, 34 deletions
diff --git a/lib/bunzip.c b/lib/bunzip.c
index a69e6181..96f7a871 100644
--- a/lib/bunzip.c
+++ b/lib/bunzip.c
@@ -27,18 +27,12 @@
#define RETVAL_OK 0
#define RETVAL_LAST_BLOCK (-1)
#define RETVAL_NOT_BZIP_DATA (-2)
-#define RETVAL_UNEXPECTED_INPUT_EOF (-3)
-#define RETVAL_UNEXPECTED_OUTPUT_EOF (-4)
-#define RETVAL_DATA_ERROR (-5)
-#define RETVAL_OUT_OF_MEMORY (-6)
-#define RETVAL_OBSOLETE_INPUT (-7)
+#define RETVAL_DATA_ERROR (-3)
+#define RETVAL_OBSOLETE_INPUT (-4)
char *bunzip_errors[]={
NULL,
- "Bad file checksum",
"Not bzip data",
- "Unexpected input EOF",
- "Unexpected output EOF",
"Data error",
"Out of memory",
"Obsolete (pre 0.9.5) bzip format not supported."
@@ -54,9 +48,6 @@ struct group_data {
// memory that persists between calls to bunzip
typedef struct {
- // For I/O error handling
- jmp_buf jmpbuf;
-
// Input stream, input buffer, input bit buffer
int in_fd, inbufCount, inbufPos;
char *inbuf;
@@ -93,7 +84,7 @@ static unsigned int get_bits(bunzip_data *bd, char bits_wanted)
// If we need to read more data from file into byte buffer, do so
if (bd->inbufPos == bd->inbufCount) {
if (0 >= (bd->inbufCount = read(bd->in_fd, bd->inbuf, IOBUF_SIZE)))
- longjmp(bd->jmpbuf, RETVAL_UNEXPECTED_INPUT_EOF);
+ error_exit("Unexpected input EOF");
bd->inbufPos = 0;
}
@@ -128,20 +119,16 @@ int read_bunzip_data(bunzip_data *bd)
char uc, mtfSymbol[256], symToByte[256], *selectors;
unsigned int *dbuf;
- // Read in header signature (borrowing mtfSymbol for temp space).
- for (i=0; i<6; i++) mtfSymbol[i] = get_bits(bd,8);
- mtfSymbol[6] = 0;
-
- // Read CRC (which is stored big endian).
+ // Read in header signature and CRC (which is stored big endian)
+ i = get_bits(bd, 24);
+ j = get_bits(bd, 24);
bd->headerCRC = get_bits(bd,32);
- // Is this the last block (with CRC for file)?
- if (!strcmp(mtfSymbol, "\x17\x72\x45\x38\x50\x90"))
- return RETVAL_LAST_BLOCK;
+ // Is this the EOF block with CRC for whole file?
+ if (i==0x177245 && j==0x385090) return RETVAL_LAST_BLOCK;
- // If it's not a valid data block, barf.
- if (strcmp(mtfSymbol, "\x31\x41\x59\x26\x53\x59"))
- return RETVAL_NOT_BZIP_DATA;
+ // Is this a valid data block?
+ if (i!=0x314159 || j!=0x265359) return RETVAL_NOT_BZIP_DATA;
dbuf = bd->dbuf;
dbufSize = bd->dbufSize;
@@ -414,7 +401,7 @@ void flush_bunzip_outbuf(bunzip_data *bd, int out_fd)
{
if (bd->outbufPos) {
if (write(out_fd, bd->outbuf, bd->outbufPos) != bd->outbufPos)
- longjmp(bd->jmpbuf,RETVAL_UNEXPECTED_OUTPUT_EOF);
+ error_exit("Unexpected output EOF");
bd->outbufPos = 0;
}
}
@@ -526,8 +513,7 @@ int start_bunzip(bunzip_data **bdp, int src_fd, char *inbuf, int len)
if (!len) i += IOBUF_SIZE;
// Allocate bunzip_data. Most fields initialize to zero.
- if (!(bd = *bdp = malloc(i))) return RETVAL_OUT_OF_MEMORY;
- memset(bd,0,sizeof(bunzip_data));
+ bd = *bdp = xzalloc(i);
if (len) {
bd->inbuf = inbuf;
bd->inbufCount = len;
@@ -545,10 +531,6 @@ int start_bunzip(bunzip_data **bdp, int src_fd, char *inbuf, int len)
bd->crc32Table[i] = c;
}
- // Setup for I/O error handling via longjmp.
- i = setjmp(bd->jmpbuf);
- if (i) return i;
-
// Ensure that file starts with "BZh".
for (i=0;i<3;i++)
if (get_bits(bd,8)!="BZh"[i]) return RETVAL_NOT_BZIP_DATA;
@@ -558,15 +540,14 @@ int start_bunzip(bunzip_data **bdp, int src_fd, char *inbuf, int len)
i = get_bits(bd, 8);
if (i<'1' || i>'9') return RETVAL_NOT_BZIP_DATA;
bd->dbufSize = 100000*(i-'0');
- if (!(bd->dbuf = malloc(bd->dbufSize * sizeof(int))))
- return RETVAL_OUT_OF_MEMORY;
+ bd->dbuf = xmalloc(bd->dbufSize * sizeof(int));
return RETVAL_OK;
}
// Example usage: decompress src_fd to dst_fd. (Stops at end of bzip data,
// not end of file.)
-char *bunzipStream(int src_fd, int dst_fd)
+void bunzipStream(int src_fd, int dst_fd)
{
bunzip_data *bd;
int i;
@@ -578,5 +559,5 @@ char *bunzipStream(int src_fd, int dst_fd)
flush_bunzip_outbuf(bd,dst_fd);
free(bd->dbuf);
free(bd);
- return bunzip_errors[-i];
+ if (i) error_exit(bunzip_errors[-i]);
}