1 /*
2 To build the snappytool binary:
3 g++ main.cpp /usr/lib/libsnappy.a -o snappytool
4 or, if you have built the C++ snappy library from source:
5 g++ main.cpp /path/to/your/snappy/.libs/libsnappy.a -o snappytool
6 after running "make" from your snappy checkout directory.
7 */
8
9 #include <errno.h>
10 #include <stdio.h>
11 #include <string.h>
12 #include <unistd.h>
13
14 #include "snappy.h"
15
16 #define N 1000000
17
18 char dst[N];
19 char src[N];
20
main(int argc,char ** argv)21 int main(int argc, char** argv) {
22 // Parse args.
23 if (argc != 2) {
24 fprintf(stderr, "exactly one of -d or -e must be given\n");
25 return 1;
26 }
27 bool decode = strcmp(argv[1], "-d") == 0;
28 bool encode = strcmp(argv[1], "-e") == 0;
29 if (decode == encode) {
30 fprintf(stderr, "exactly one of -d or -e must be given\n");
31 return 1;
32 }
33
34 // Read all of stdin into src[:s].
35 size_t s = 0;
36 while (1) {
37 if (s == N) {
38 fprintf(stderr, "input too large\n");
39 return 1;
40 }
41 ssize_t n = read(0, src+s, N-s);
42 if (n == 0) {
43 break;
44 }
45 if (n < 0) {
46 fprintf(stderr, "read error: %s\n", strerror(errno));
47 // TODO: handle EAGAIN, EINTR?
48 return 1;
49 }
50 s += n;
51 }
52
53 // Encode or decode src[:s] to dst[:d], and write to stdout.
54 size_t d = 0;
55 if (encode) {
56 if (N < snappy::MaxCompressedLength(s)) {
57 fprintf(stderr, "input too large after encoding\n");
58 return 1;
59 }
60 snappy::RawCompress(src, s, dst, &d);
61 } else {
62 if (!snappy::GetUncompressedLength(src, s, &d)) {
63 fprintf(stderr, "could not get uncompressed length\n");
64 return 1;
65 }
66 if (N < d) {
67 fprintf(stderr, "input too large after decoding\n");
68 return 1;
69 }
70 if (!snappy::RawUncompress(src, s, dst)) {
71 fprintf(stderr, "input was not valid Snappy-compressed data\n");
72 return 1;
73 }
74 }
75 write(1, dst, d);
76 return 0;
77 }
78