int LZ77_Decompress( UINT8* inBuf, int inSize, UINT8* outBuf, int outSize, WRITE_MEMORY_FUNCT writeMem, READ_MEMORY_FUNCT readMem)
{
UINT8* inBufEnd = inBuf + inSize;
UINT8* outBufEnd = outBuf + outSize;
int counter;
int currPos = 0;
UINT8 window[ WINSIZE ];
for(counter = 0; counter < WINSIZE; counter ++)
{
window[ counter ] = ' ';
}
//#define CHECKEDREAD(x) if(inBuf >= inBufEnd ) { DebugBreak(); return -1; } x
//#define CHECKEDWRITE(x) if(outBuf >= outBufEnd) { DebugBreak(); return -1; } x
#define CHECKEDREAD(x,y) if(inBuf >= inBufEnd ) return -1; if(readMem != NULL) readMem ( (UINT32)y, 1, &x ); else x = *y
#define CHECKEDWRITE(x,y) if(outBuf >= outBufEnd) return -1; if(writeMem != NULL) writeMem( (UINT32)x, 1, &y ); else *x = y
while(inBuf < inBufEnd)
{
//
// Get BitMap and data following it.
//
UINT8 bitMap;
CHECKEDREAD(bitMap, inBuf++);
//
// Go through and decode data.
//
for(counter = 0; counter < 8 && outBuf < outBufEnd; counter++)
{
//
// It's a code, so decode it and copy the data.
//
if(!BITSET(bitMap, counter))
{
UINT8 byte1;
UINT8 byte2;
CHECKEDREAD(byte1, inBuf++);
CHECKEDREAD(byte2, inBuf++);
int length = LENGTH(byte2);
int offset = OFFSET(byte1, byte2);
//
// Copy data from window.
//
while(length)
{
byte1 = window[ FAKE2REAL_POS(offset) ];
window[ FAKE2REAL_POS(currPos) ] = byte1;
CHECKEDWRITE(outBuf++, byte1);
currPos++;
offset++;
length--;
}
}
else
{
UINT8 byte1;
CHECKEDREAD(byte1, inBuf++);
window[ FAKE2REAL_POS(currPos) ] = byte1;
CHECKEDWRITE(outBuf++, byte1);
currPos++;
}
}
}
#undef CHECKEDREAD
#undef CHECKEDWRITE
return 1;
}
int
main(int argc, char **argv)
{
int fifo = -1;
int nfd = 0;
int writepipe[2] = {-1};
int readpipe[2] = {-1};
struct passwd *pwent = NULL;
pid_t child = -1;
fd_set rfds;
pwent = getpwuid(getuid());
if (!pwent || !pwent->pw_dir || !pwent->pw_dir[0])
return perror("pwent"), EXIT_FAILURE;
strncpy(path, pwent->pw_dir, PATH_MAX);
strncat(path, "/.sam.fifo", PATH_MAX);
if (pipe(writepipe) != 0 || pipe(readpipe) != 0)
return perror("pipe"), EXIT_FAILURE;
unlink(path);
if (mkfifo(path, 0600) != 0)
return perror("mkfifo"), EXIT_FAILURE;
atexit(cleanup);
fifo = open(path, O_RDWR);
if (fifo < 0)
return perror("open"), EXIT_FAILURE;
child = fork();
if (child == 0){
close(PARENT_WRITE);
close(PARENT_READ);
dup2(CHILD_READ, STDIN_FILENO); close(CHILD_READ);
dup2(CHILD_WRITE, STDOUT_FILENO); close(CHILD_WRITE);
execlp("sam", "sam", "-R", NULL);
return EXIT_FAILURE;
} else if (child < 0){
perror("fork");
return EXIT_FAILURE;
}
close(CHILD_READ);
close(CHILD_WRITE);
FD_ZERO(&rfds);
FD_SET(STDIN_FILENO, &rfds);
FD_SET(fifo, &rfds);
FD_SET(PARENT_READ, &rfds);
nfd = MAX(STDIN_FILENO, MAX(PARENT_READ, fifo)) + 1;
while (select(nfd, &rfds, NULL, NULL, NULL) >= 0){
ssize_t count = 0;
char buf[8192];
if (FD_ISSET(STDIN_FILENO, &rfds)){
count = read(STDIN_FILENO, buf, 8192);
if (count <= 0)
exit(EXIT_SUCCESS);
CHECKEDWRITE(PARENT_WRITE, buf, count);
}
if (FD_ISSET(fifo, &rfds)){
memset(buf, 0, 256);
count = read(fifo, buf, 253);
if (count <= 0)
exit(EXIT_SUCCESS);
CHECKEDWRITE(STDOUT_FILENO, "\x19\xff\x00", 3);
CHECKEDWRITE(STDOUT_FILENO, buf, 255);
}
if (FD_ISSET(PARENT_READ, &rfds)){
count = read(PARENT_READ, buf, 8192);
if (count <= 0)
exit(EXIT_SUCCESS);
CHECKEDWRITE(STDOUT_FILENO, buf, count);
}
FD_ZERO(&rfds);
FD_SET(STDIN_FILENO, &rfds);
FD_SET(fifo, &rfds);
FD_SET(PARENT_READ, &rfds);
}
return EXIT_SUCCESS;
}
