c57ec3795

Rob Landley

2006-04-10

SOURCE BUG Duration: 21s

Subject

Patch from Rob Sullivan to consolidate crc32 table generation.

SOURCE BUG

This commit was genuinely broken at the time (not related to our build system): scripts/config/mkconfigs.c (2005-08-01 - 2006-10-05 arasi) uretilen bbconfigopts.h icine .config satirlarini kacissiz, ham newline'larla gömüyordu - gecerli C degildi, busybox'un kendi bb_mkdep araci bile parse edemiyordu (7d219aab7 ile duzeltildi, mkconfigs shell scripte cevrildi)

→ Bu hatanin tam hikayesini ve duzeltme diffini gor

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

archival/gzip.c +10 -25 archival/libunarchive/decompress_bunzip2.c +5 -10 archival/libunarchive/decompress_unzip.c +7 -35 include/libbb.h +2 -0 libbb/Makefile.in +1 -1 libbb/crc32.c +40 -0

archival/gzip.c+10 -25

@@ -293,6 +293,7 @@ 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)
@@ -344,32 +345,13 @@ 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 +360,7 @@ 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 +1205,9 @@ 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;

@@ -2416,7 +2401,7 @@ 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)

archival/libunarchive/decompress_bunzip2.c+5 -10

@@ -84,8 +84,8 @@ typedef struct {

	/* The CRC values stored in the block header and calculated from the data */

-	unsigned int crc32Table[256],headerCRC, totalCRC, writeCRC;
-
+	uint32_t headerCRC, totalCRC, writeCRC;
+	uint32_t *crc32Table;
	/* Intermediate buffer and its size (in bytes) */

	unsigned int *dbuf, dbufSize;
@@ -620,7 +620,7 @@ decode_next_byte:
	bd->writeCount=previous;
	return (previous!=RETVAL_LAST_BLOCK) ? previous : gotcount;
	}
-	bd->writeCRC=0xffffffffUL;
+	bd->writeCRC=~0;
	pos=bd->writePos;
	current=bd->writeCurrent;
	goto decode_next_byte;
@@ -634,7 +634,7 @@ static int start_bunzip(bunzip_data *bdp, int in_fd, unsigned char inbuf,
	int len)
	{
	bunzip_data *bd;
-	unsigned int i,j,c;
+	unsigned int i;
	const unsigned int BZh0=(((unsigned int)'B')<<24)+(((unsigned int)'Z')<<16)
	+(((unsigned int)'h')<<8)+(unsigned int)'0';

@@ -657,12 +657,7 @@ static int start_bunzip(bunzip_data *bdp, int in_fd, unsigned char inbuf,

	/* Init the CRC32 table (big endian) */

-	for(i=0;i<256;i++) {
-	c=i<<24;
-	for(j=8;j;j--)
-	c=c&0x80000000 ? (c<<1)^0x04c11db7 : (c<<1);
-	bd->crc32Table[i]=c;
-	}
+	bd->crc32Table = bb_crc32_filltable(1);

	/* Setup for I/O error handling via longjmp */

archival/libunarchive/decompress_unzip.c+7 -35

@@ -95,8 +95,8 @@ static unsigned int gunzip_outbuf_count; /* bytes in output buffer */
	enum { gunzip_wsize = 0x8000 };
	static unsigned char *gunzip_window;

-	static unsigned int *gunzip_crc_table;
-	unsigned int gunzip_crc;
+	static uint32_t *gunzip_crc_table;
+	uint32_t gunzip_crc;

	/* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
	#define BMAX 16 /* maximum bit length of any code (16 for explode) */
@@ -168,35 +168,6 @@ static unsigned int fill_bitbuffer(unsigned int bitbuffer, unsigned int *current
	return(bitbuffer);
	}

-	static void make_gunzip_crc_table(void)
-	{
-	const unsigned int poly = 0xedb88320; /* polynomial exclusive-or pattern */
-	unsigned short i; /* counter for all possible eight bit values */
-
-	/* initial shift register value */
-	gunzip_crc = 0xffffffffL;
-	gunzip_crc_table = (unsigned int ) xmalloc(256 sizeof(unsigned int));
-
-	/* Compute and print table of CRC's, five per line */
-	for (i = 0; i < 256; i++) {
-	unsigned int table_entry; /* crc shift register */
-	unsigned char k; /* byte being shifted into crc apparatus */
-
-	table_entry = 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--) {
-	if (table_entry & 1) {
-	table_entry = (table_entry >> 1) ^ poly;
-	} else {
-	table_entry >>= 1;
-	}
-	}
-	gunzip_crc_table[i] = table_entry;
-	}
-	}
-
	/*
	* Free the malloc'ed tables built by huft_build(), which makes a linked
	* list of the tables it made, with the links in a dummy first entry of
@@ -922,8 +893,9 @@ int inflate_unzip(int in, int out)
	gunzip_bb = 0;

	/* Create the crc table */
-	make_gunzip_crc_table();
-
+	gunzip_crc_table = bb_crc32_filltable(0);
+	gunzip_crc = ~0;
+
	/* Allocate space for buffer */
	bytebuffer = xmalloc(bytebuffer_max);

@@ -955,7 +927,7 @@ int inflate_unzip(int in, int out)

	int inflate_gunzip(int in, int out)
	{
-	unsigned int stored_crc = 0;
+	uint32_t stored_crc = 0;
	unsigned int count;

	inflate_unzip(in, out);
@@ -972,7 +944,7 @@ int inflate_gunzip(int in, int out)
	}

	/* Validate decompression - crc */
-	if (stored_crc != (gunzip_crc ^ 0xffffffffL)) {
+	if (stored_crc != (~gunzip_crc)) {
	bb_error_msg("crc error");
	return -1;
	}

include/libbb.h+2 -0

@@ -508,6 +508,8 @@ void md5_begin(md5_ctx_t *ctx);
	void md5_hash(const void data, size_t length, md5_ctx_t ctx);
	void md5_end(void resbuf, md5_ctx_t *ctx);

+	extern uint32_t *bb_crc32_filltable (int endian);
+
	/* busybox.h will include dmalloc later for us, else include it here. */
	#if !defined _BB_INTERNAL_H_ && defined DMALLOC
	#include <dmalloc.h>

libbb/Makefile.in+1 -1

@@ -13,7 +13,7 @@ LIBBB-n:=
	LIBBB-y:= \
	bb_asprintf.c ask_confirmation.c change_identity.c chomp.c \
	compare_string_array.c concat_path_file.c copy_file.c copyfd.c \
-	create_icmp_socket.c create_icmp6_socket.c \
+	crc32.c create_icmp_socket.c create_icmp6_socket.c \
	device_open.c dump.c error_msg.c error_msg_and_die.c find_mount_point.c \
	find_pid_by_name.c find_root_device.c fgets_str.c full_read.c \
	full_write.c get_last_path_component.c get_line_from_file.c \

libbb/crc32.c+40 -0

@@ -0,0 +1,40 @@
+	/* vi: set sw=4 ts=4: */
+	/*
+	* CRC32 table fill function
+	* Copyright (C) 2006 by Rob Sullivan <[email protected]>
+	* (I can't really claim much credit however, as the algorithm is
+	* very well-known)
+	*
+	* The following function creates a CRC32 table depending on whether
+	* a big-endian (0x04c11db7) or little-endian (0xedb88320) CRC32 is
+	* required. Admittedly, there are other CRC32 polynomials floating
+	* around, but Busybox doesn't use them.
+	*
+	* endian = 1: big-endian
+	* endian = 0: little-endian
+	*/
+
+	#include <stdio.h>
+	#include <stdlib.h>
+	#include "libbb.h"
+
+	uint32_t *bb_crc32_filltable (int endian) {
+
+	uint32_t crc_table = xmalloc(256 sizeof(uint32_t));
+	uint32_t polynomial = endian ? 0x04c11db7 : 0xedb88320;
+	uint32_t c;
+	int i, j;
+
+	for (i = 0; i < 256; i++) {
+	c = endian ? (i << 24) : i;
+	for (j = 8; j; j--) {
+	if (endian)
+	c = (c&0x80000000) ? ((c << 1) ^ polynomial) : (c << 1);
+	else
+	c = (c&1) ? ((c >> 1) ^ polynomial) : (c >> 1);
+	}
+	*crc_table++ = c;
+	}
+
+	return crc_table - 256;
+	}