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/*
To build the snappytool binary:
g++ main.cpp /usr/lib/libsnappy.a -o snappytool
or, if you have built the C++ snappy library from source:
g++ main.cpp /path/to/your/snappy/.libs/libsnappy.a -o snappytool
after running "make" from your snappy checkout directory.
*/
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "snappy.h"
#define N 1000000
char dst[N];
char src[N];
int main(int argc, char** argv) {
// Parse args.
if (argc != 2) {
fprintf(stderr, "exactly one of -d or -e must be given\n");
return 1;
}
bool decode = strcmp(argv[1], "-d") == 0;
bool encode = strcmp(argv[1], "-e") == 0;
if (decode == encode) {
fprintf(stderr, "exactly one of -d or -e must be given\n");
return 1;
}
// Read all of stdin into src[:s].
size_t s = 0;
while (1) {
if (s == N) {
fprintf(stderr, "input too large\n");
return 1;
}
ssize_t n = read(0, src+s, N-s);
if (n == 0) {
break;
}
if (n < 0) {
fprintf(stderr, "read error: %s\n", strerror(errno));
// TODO: handle EAGAIN, EINTR?
return 1;
}
s += n;
}
// Encode or decode src[:s] to dst[:d], and write to stdout.
size_t d = 0;
if (encode) {
if (N < snappy::MaxCompressedLength(s)) {
fprintf(stderr, "input too large after encoding\n");
return 1;
}
snappy::RawCompress(src, s, dst, &d);
} else {
if (!snappy::GetUncompressedLength(src, s, &d)) {
fprintf(stderr, "could not get uncompressed length\n");
return 1;
}
if (N < d) {
fprintf(stderr, "input too large after decoding\n");
return 1;
}
if (!snappy::RawUncompress(src, s, dst)) {
fprintf(stderr, "input was not valid Snappy-compressed data\n");
return 1;
}
}
write(1, dst, d);
return 0;
}
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