- use bb_xchdir instead of ignoring eventual errors of chdir

[oweals/busybox.git] / archival / gzip.c

diff --git a/archival/gzip.c b/archival/gzip.c
index fa6e85b666761bbbb18345a684390107e2486e07..91b2948917f5658b6ecce5411b5ae3f86711cfd2 100644 (file)
--- a/archival/gzip.c
+++ b/archival/gzip.c
@@ -16,11 +16,7 @@
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-/* These defines are very important for BusyBox.  Without these,
- * huge chunks of ram are pre-allocated making the BusyBox bss
- * size Freaking Huge(tm), which is a bad thing.*/
 #define SMALL_MEM
-#define DYN_ALLOC
 
 #include <stdlib.h>
 #include <stdio.h>
@@ -87,17 +83,11 @@ typedef unsigned long ulg;
 #  endif
 #endif
 
-#ifdef DYN_ALLOC
 #  define DECLARE(type, array, size)  static type * array
 #  define ALLOC(type, array, size) { \
-      array = (type*)xcalloc((size_t)(((size)+1L)/2), 2*sizeof(type)); \
+      array = (type*)xzalloc((size_t)(((size)+1L)/2) * 2*sizeof(type)); \
    }
 #  define FREE(array) {free(array), array=NULL;}
-#else
-#  define DECLARE(type, array, size)  static type array[size]
-#  define ALLOC(type, array, size)
-#  define FREE(array)
-#endif
 
 #define tab_suffix window
 #define tab_prefix prev        /* hash link (see deflate.c) */
@@ -293,6 +283,7 @@ static int ofd;                     /* output file descriptor */
 static unsigned insize;        /* valid bytes in inbuf */
 static unsigned outcnt;        /* bytes in output buffer */
 
+static uint32_t *crc_32_tab;
 
 /* Output a 16 bit value, lsb first */
 static void put_short(ush w)
@@ -333,7 +324,7 @@ static void write_buf(int fd, void *buf, unsigned cnt)
        unsigned n;
 
        while ((n = write(fd, buf, cnt)) != cnt) {
-               if (n == (unsigned) (-1)) bb_error_msg_and_die("can't write");
+               if (n == (unsigned) (-1)) bb_error_msg_and_die(bb_msg_write_error);
                cnt -= n;
                buf = (void *) ((char *) buf + n);
        }
@@ -344,32 +335,13 @@ static void write_buf(int fd, void *buf, unsigned cnt)
  * pointer, then initialize the crc shift register contents instead.
  * Return the current crc in either case.
  */
-static ulg updcrc(uch * s, unsigned n)
+static uint32_t updcrc(uch * s, unsigned n)
 {
-       static ulg crc = (ulg) 0xffffffffL;     /* shift register contents */
-       register ulg c;         /* temporary variable */
-       static unsigned long crc_32_tab[256];
-
-       if (crc_32_tab[1] == 0x00000000L) {
-               unsigned long csr;      /* crc shift register */
-               const unsigned long e = 0xedb88320L;    /* polynomial exclusive-or pattern */
-               int i;                  /* counter for all possible eight bit values */
-               int k;                  /* byte being shifted into crc apparatus */
-
-               /* Compute table of CRC's. */
-               for (i = 1; i < 256; i++) {
-                       csr = i;
-                       /* The idea to initialize the register with the byte instead of
-                          * zero was stolen from Haruhiko Okumura's ar002
-                        */
-                       for (k = 8; k; k--)
-                               csr = csr & 1 ? (csr >> 1) ^ e : csr >> 1;
-                       crc_32_tab[i] = csr;
-               }
-       }
+       static uint32_t crc = ~0;       /* shift register contents */
+       uint32_t c;             /* temporary variable */
 
        if (s == NULL) {
-               c = 0xffffffffL;
+               c = ~0;
        } else {
                c = crc;
                if (n)
@@ -378,7 +350,7 @@ static ulg updcrc(uch * s, unsigned n)
                        } while (--n);
        }
        crc = c;
-       return c ^ 0xffffffffL; /* (instead of ~c for 64-bit machines) */
+       return ~c;
 }
 
 /* bits.c -- output variable-length bit strings
@@ -1223,6 +1195,9 @@ int gzip_main(int argc, char **argv)
        ALLOC(uch, window, 2L * WSIZE);
        ALLOC(ush, tab_prefix, 1L << BITS);
 
+       /* Initialise the CRC32 table */
+       crc_32_tab = bb_crc32_filltable(0);
+       
        clear_bufs();
        part_nb = 0;
 
@@ -1243,8 +1218,8 @@ int gzip_main(int argc, char **argv)
                                inFileNum = STDIN_FILENO;
                                outFileNum = STDOUT_FILENO;
                        } else {
-                               inFileNum = open(argv[i], O_RDONLY);
-                               if (inFileNum < 0 || fstat(inFileNum, &statBuf) < 0)
+                               inFileNum = bb_xopen3(argv[i], O_RDONLY, 0);
+                               if (fstat(inFileNum, &statBuf) < 0)
                                        bb_perror_msg_and_die("%s", argv[i]);
                                time_stamp = statBuf.st_ctime;
                                ifile_size = statBuf.st_size;
@@ -2416,7 +2391,7 @@ static void set_file_type(void)
  */
 
 
-static ulg crc;                        /* crc on uncompressed file data */
+static uint32_t crc;                   /* crc on uncompressed file data */
 static long header_bytes;      /* number of bytes in gzip header */
 
 static void put_long(ulg n)