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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <getopt.h>
#include <string.h>
#include "smaz2.h"
int debug = 0;
#define BUF_SIZE 4096
#define SAVE_SIZE 14 // 3 + max strlen in words[]
int main(int argc, char **argv) {
int decompress = 0, trace = 0, sure = 0;
char opt; // man getopt.3
extern char *optarg;
static const char *const opts="hdvf";
while ( (opt = getopt(argc, argv, opts)) != -1) {
switch (opt) {
case 'h':
fprintf(stderr, "Compress or decompress smaz2, stdin to stdout.\n"
"Usage:\n"
"%s [-%s]\n"
"-d - Decompress\n"
"-h - Print this help\n"
"-v - Be one level more verbose\n"
"-f - read/write compressed data from/to a TTY\n"
"Return codes:\n"
"0 - success\n"
"1 - internal error or malformed input\n"
"2 - read error\n"
"3 - write error\n"
"4 - compressed data to/from TTY without -f\n"
, argv[0], opts);
exit(0);
break;
case 'd':
decompress = 1;
break;
case 'v':
trace ++;
debug = trace>1;
break;
case 'f':
sure = 1;
break;
default:
fprintf(stderr, "invalid option -%c\n", opt);
}
}
if (!sure && isatty(decompress?0:1)) {
fprintf(stderr, "warning: %s connected to TTY\n(pass -f to ignore)\n",decompress?"stdin":"stdout");
exit(4);
}
unsigned char ibuf[BUF_SIZE+SAVE_SIZE], obuf[BUF_SIZE*3];
unsigned char sbuf[SAVE_SIZE]; int save = 0;
while (1) {
if (save) memcpy(ibuf,sbuf,save);
ssize_t numRead = read(0, ibuf+save, BUF_SIZE); // sizeof(char) === 1
if (trace) fprintf(stderr, "read %liB", numRead);
if (trace && save) fprintf(stderr, ", plus last %iB of previous buffer\n", save);
if (trace &&!save) fprintf(stderr, "\n");
if (numRead == -1) {
perror("read");
exit(2);
}
int end = save && !numRead;
numRead += save;
save = 0;
if (!numRead) break;
if (!end){ if (decompress) {
// check for end malformation/incomplete byte sequences
// 80-ff: bigraphs
// 01-05: verbatim, n chars
// 06-08: word with maybe space, 1 char
// otherwise (00,09-7f) verbatim
save = 0;
if(0){}
else if (ibuf[numRead-5] == '\x05') save = 5;
else if (ibuf[numRead-4] == '\x04') save = 4;
else if (ibuf[numRead-3] == '\x03') save = 3;
else if (ibuf[numRead-2] == '\x02') save = 2;
else if (0
|| ibuf[numRead-1] == '\x01'
|| ibuf[numRead-1] == '\x06'
|| ibuf[numRead-1] == '\x07'
|| ibuf[numRead-1] == '\x08'
) save = 1;
} else {
// ideally, would check for cut words or digraphs
// actually, just tries to keep the last few alphabet chars
int i = numRead-1;
while (i>=numRead-SAVE_SIZE && ibuf[i]>='a' && ibuf[i]<='z') i--;
save = numRead-1 - i;
} }
ssize_t numIn = numRead - save;
if (save) memcpy(sbuf, ibuf+numIn, save);
if (save && trace) fprintf(stderr, "saved %iB; now %liB\n",save, numIn);
ssize_t numOut = decompress
? smaz2_decompress(obuf, BUF_SIZE*2, ibuf, numIn)
: smaz2_compress (obuf, BUF_SIZE*2, ibuf, numIn)
;
if (!numOut) {
fprintf(stderr, "warning: malformed input or internal error\n");
exit(1);
}
ssize_t numWrite = write(1, obuf, numOut);
if (numWrite != numOut) {
perror("write - partial/failed write");
if (numWrite > 0) fprintf(stderr,"(wrote %liB)\n",numWrite);
exit(3);
}
if (trace) fprintf(stderr, "wrote %liB (%.2f%%)\n", numOut, 100.0*numOut/numIn);
}
if (trace) fprintf(stderr, "closed\n");
}
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