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moved biggest stack buffers to malloc space, or made their size configurable

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(8k of shell line edit buffer is an overkill)

# make ARCH=i386 bloatcheck
function                                             old     new   delta
read_line_input                                     3933    3967     +34
ifaddrlist                                           348     345      -3
do_loadfont                                          208     191     -17
edit_file                                            840     819     -21
.rodata                                           129112  129080     -32
uncompress                                          1305    1268     -37
loadfont_main                                        566     495     -71
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/6 up/down: 34/-181)          Total: -147 bytes
This commit is contained in:
Denis Vlasenko
2007-06-10 15:08:44 +00:00
parent d4fea900bd
commit e8a0788b24
8 changed files with 179 additions and 149 deletions
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94
archival/libunarchive/decompress_uncompress.c
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@@ -7,7 +7,6 @@
* (see disclaimer below)
*/
/* (N)compress42.c - File compression ala IEEE Computer, Mar 1992.
*
* Authors:
@@ -34,53 +33,48 @@
#define OBUFSIZ 2048
/* Defines for third byte of header */
#define MAGIC_1 (char_type)'\037' /* First byte of compressed file */
#define MAGIC_2 (char_type)'\235' /* Second byte of compressed file */
#define BIT_MASK 0x1f /* Mask for 'number of compresssion bits' */
/* Masks 0x20 and 0x40 are free. */
/* I think 0x20 should mean that there is */
/* a fourth header byte (for expansion). */
#define BLOCK_MODE 0x80 /* Block compresssion if table is full and */
/* compression rate is dropping flush tables */
/* the next two codes should not be changed lightly, as they must not */
/* lie within the contiguous general code space. */
#define FIRST 257 /* first free entry */
#define CLEAR 256 /* table clear output code */
#define BIT_MASK 0x1f /* Mask for 'number of compresssion bits' */
/* Masks 0x20 and 0x40 are free. */
/* I think 0x20 should mean that there is */
/* a fourth header byte (for expansion). */
#define BLOCK_MODE 0x80 /* Block compression if table is full and */
/* compression rate is dropping flush tables */
/* the next two codes should not be changed lightly, as they must not */
/* lie within the contiguous general code space. */
#define FIRST 257 /* first free entry */
#define CLEAR 256 /* table clear output code */
#define INIT_BITS 9 /* initial number of bits/code */
#define INIT_BITS 9 /* initial number of bits/code */
/* machine variants which require cc -Dmachine: pdp11, z8000, DOS */
#define FAST
#define HBITS 17 /* 50% occupancy */
#define HSIZE (1<<HBITS)
#define HMASK (HSIZE-1)
#define HPRIME 9941
#define BITS 16
#undef MAXSEG_64K
#define MAXCODE(n) (1L << (n))
#define htabof(i) htab[i]
#define codetabof(i) codetab[i]
#define tab_prefixof(i) codetabof(i)
#define tab_suffixof(i) ((unsigned char *)(htab))[i]
#define de_stack ((unsigned char *)&(htab[HSIZE-1]))
#define clear_htab() memset(htab, -1, HSIZE)
#define clear_tab_prefixof() memset(codetab, 0, 256);
#define HBITS 17 /* 50% occupancy */
#define HSIZE (1<<HBITS)
#define HMASK (HSIZE-1) /* unused */
#define HPRIME 9941 /* unused */
#define BITS 16
#define BITS_STR "16"
#undef MAXSEG_64K /* unused */
#define MAXCODE(n) (1L << (n))
#define htabof(i) htab[i]
#define codetabof(i) codetab[i]
#define tab_prefixof(i) codetabof(i)
#define tab_suffixof(i) ((unsigned char *)(htab))[i]
#define de_stack ((unsigned char *)&(htab[HSIZE-1]))
#define clear_tab_prefixof() memset(codetab, 0, 256)
/*
* Decompress stdin to stdout. This routine adapts to the codes in the
* file building the "string" table on-the-fly; requiring no table to
* be stored in the compressed file. The tables used herein are shared
* with those of the compress() routine. See the definitions above.
* be stored in the compressed file.
*/
USE_DESKTOP(long long) int
uncompress(int fd_in, int fd_out)
{
USE_DESKTOP(long long total_written = 0;)
USE_DESKTOP(long long) int retval = -1;
unsigned char *stackp;
long code;
int finchar;
@@ -96,10 +90,10 @@ uncompress(int fd_in, int fd_out)
long maxmaxcode;
int n_bits;
int rsize = 0;
RESERVE_CONFIG_UBUFFER(inbuf, IBUFSIZ + 64);
RESERVE_CONFIG_UBUFFER(outbuf, OBUFSIZ + 2048);
unsigned char htab[HSIZE];
unsigned short codetab[HSIZE];
unsigned char *inbuf; /* were eating insane amounts of stack - */
unsigned char *outbuf; /* bad for some embedded targets */
unsigned char *htab;
unsigned short *codetab;
/* Hmm, these were statics - why?! */
/* user settable max # bits/code */
@@ -107,8 +101,10 @@ uncompress(int fd_in, int fd_out)
/* block compress mode -C compatible with 2.0 */
int block_mode; /* = BLOCK_MODE; */
memset(inbuf, 0, IBUFSIZ + 64);
memset(outbuf, 0, OBUFSIZ + 2048);
inbuf = xzalloc(IBUFSIZ + 64);
outbuf = xzalloc(OBUFSIZ + 2048);
htab = xzalloc(HSIZE); /* wsn't zeroed out before, maybe can xmalloc? */
codetab = xzalloc(HSIZE * sizeof(codetab[0]));
insize = 0;
@@ -116,7 +112,7 @@ uncompress(int fd_in, int fd_out)
* to do some cleanup (e.g. delete incomplete unpacked file etc) */
if (full_read(fd_in, inbuf, 1) != 1) {
bb_error_msg("short read");
return -1;
goto err;
}
maxbits = inbuf[0] & BIT_MASK;
@@ -125,8 +121,8 @@ uncompress(int fd_in, int fd_out)
if (maxbits > BITS) {
bb_error_msg("compressed with %d bits, can only handle "
"%d bits", maxbits, BITS);
return -1;
BITS_STR" bits", maxbits);
goto err;
}
n_bits = INIT_BITS;
@@ -140,7 +136,7 @@ uncompress(int fd_in, int fd_out)
free_ent = ((block_mode) ? FIRST : 256);
/* As above, initialize the first 256 entries in the table. */
clear_tab_prefixof();
/*clear_tab_prefixof(); - done by xzalloc */
for (code = 255; code >= 0; --code) {
tab_suffixof(code) = (unsigned char) code;
@@ -232,7 +228,7 @@ uncompress(int fd_in, int fd_out)
insize, posbits, p[-1], p[0], p[1], p[2], p[3],
(posbits & 07));
bb_error_msg("uncompress: corrupt input");
return -1;
goto err;
}
*--stackp = (unsigned char) finchar;
@@ -299,7 +295,11 @@ uncompress(int fd_in, int fd_out)
USE_DESKTOP(total_written += outpos;)
}
RELEASE_CONFIG_BUFFER(inbuf);
RELEASE_CONFIG_BUFFER(outbuf);
return USE_DESKTOP(total_written) + 0;
retval = USE_DESKTOP(total_written) + 0;
err:
free(inbuf);
free(outbuf);
free(htab);
free(codetab);
return retval;
}