Commit | Line | Data |
---|---|---|
d07a80dc JA |
1 | /* |
2 | * Use vmsplice to splice data from a pipe to user space memory. | |
3 | */ | |
4 | #include <stdio.h> | |
5 | #include <stdlib.h> | |
6 | #include <unistd.h> | |
7 | #include <limits.h> | |
8 | #include <string.h> | |
9 | #include <getopt.h> | |
0a6ff83b | 10 | #include <fcntl.h> |
d07a80dc JA |
11 | #include <sys/poll.h> |
12 | #include <sys/types.h> | |
13 | ||
14 | #include "splice.h" | |
15 | ||
16 | static int do_dump; | |
17 | static int splice_flags; | |
18 | ||
19 | int do_vmsplice(int fd, void *buf, int len) | |
20 | { | |
21 | struct pollfd pfd = { .fd = fd, .events = POLLIN, }; | |
22 | struct iovec iov; | |
23 | int written; | |
24 | int ret; | |
25 | ||
26 | iov.iov_base = buf; | |
27 | iov.iov_len = len; | |
28 | ret = 0; | |
29 | ||
30 | while (len) { | |
31 | /* | |
32 | * in a real app you'd be more clever with poll of course, | |
33 | * here we are basically just blocking on output room and | |
34 | * not using the free time for anything interesting. | |
35 | */ | |
36 | if (poll(&pfd, 1, -1) < 0) | |
37 | return error("poll"); | |
38 | ||
39 | written = vmsplice(fd, &iov, 1, splice_flags); | |
40 | ||
41 | if (written < 0) | |
42 | return error("vmsplice"); | |
43 | else if (!written) | |
44 | break; | |
45 | ||
46 | len -= written; | |
47 | ret += written; | |
48 | if (len) { | |
49 | iov.iov_len -= written; | |
50 | iov.iov_base += written; | |
51 | } | |
52 | } | |
53 | ||
54 | return ret; | |
55 | } | |
56 | ||
57 | static int usage(char *name) | |
58 | { | |
59 | fprintf(stderr, "| %s [-d(ump)]\n", name); | |
60 | return 1; | |
61 | } | |
62 | ||
63 | static int parse_options(int argc, char *argv[]) | |
64 | { | |
65 | int c, index = 1; | |
66 | ||
67 | while ((c = getopt(argc, argv, "d")) != -1) { | |
68 | switch (c) { | |
69 | case 'd': | |
70 | do_dump = 1; | |
71 | index++; | |
72 | break; | |
73 | default: | |
74 | return -1; | |
75 | } | |
76 | } | |
77 | ||
78 | return index; | |
79 | } | |
80 | ||
81 | static void hexdump(unsigned char *buf, int len) | |
82 | { | |
83 | int i; | |
84 | ||
85 | for (i = 0; i < len; i++) | |
86 | printf("%02x", buf[i]); | |
87 | printf("\n"); | |
88 | } | |
89 | ||
90 | int main(int argc, char *argv[]) | |
91 | { | |
92 | unsigned char *buf; | |
93 | int ret; | |
94 | ||
95 | if (parse_options(argc, argv) < 0) | |
96 | return usage(argv[0]); | |
97 | ||
98 | if (check_input_pipe()) | |
99 | return usage(argv[0]); | |
100 | ||
101 | buf = malloc(4096); | |
102 | ||
103 | memset(buf, 0, 4096); | |
104 | ||
105 | ret = do_vmsplice(STDIN_FILENO, buf, 4096); | |
106 | if (ret < 0) | |
107 | return 1; | |
108 | ||
109 | printf("splice %d\n", ret); | |
110 | ||
111 | if (do_dump) | |
112 | hexdump(buf, ret); | |
113 | ||
114 | return 0; | |
115 | } |