Commit | Line | Data |
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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; | |
ef0e4210 JA |
17 | static int do_ascii; |
18 | static int do_zeromap; | |
d07a80dc JA |
19 | static int splice_flags; |
20 | ||
ef0e4210 JA |
21 | static int do_vmsplice_unmap(int fd, unsigned char *buf, int len) |
22 | { | |
23 | struct iovec iov = { | |
24 | .iov_base = buf, | |
25 | .iov_len = len, | |
26 | }; | |
27 | ||
28 | return svmsplice(fd, &iov, 1, SPLICE_F_UNMAP); | |
29 | } | |
30 | ||
c972eeeb | 31 | static int do_vmsplice(int fd, void **buf, int len) |
d07a80dc JA |
32 | { |
33 | struct pollfd pfd = { .fd = fd, .events = POLLIN, }; | |
c972eeeb JA |
34 | struct iovec iov = { |
35 | .iov_base = *buf, | |
36 | .iov_len = len, | |
37 | }; | |
d07a80dc | 38 | int written; |
c972eeeb | 39 | int ret = 0; |
d07a80dc JA |
40 | |
41 | while (len) { | |
42 | /* | |
43 | * in a real app you'd be more clever with poll of course, | |
44 | * here we are basically just blocking on output room and | |
45 | * not using the free time for anything interesting. | |
46 | */ | |
47 | if (poll(&pfd, 1, -1) < 0) | |
48 | return error("poll"); | |
49 | ||
13b72067 | 50 | written = svmsplice(fd, &iov, 1, splice_flags); |
c972eeeb JA |
51 | |
52 | if (!ret) | |
53 | *buf = iov.iov_base; | |
d07a80dc JA |
54 | |
55 | if (written < 0) | |
56 | return error("vmsplice"); | |
57 | else if (!written) | |
58 | break; | |
59 | ||
60 | len -= written; | |
61 | ret += written; | |
62 | if (len) { | |
63 | iov.iov_len -= written; | |
64 | iov.iov_base += written; | |
65 | } | |
66 | } | |
67 | ||
68 | return ret; | |
69 | } | |
70 | ||
71 | static int usage(char *name) | |
72 | { | |
ef0e4210 | 73 | fprintf(stderr, "| %s [-d(ump)] [-a(ascii)] [-m(ap)] [-z(eromap)]\n", name); |
d07a80dc JA |
74 | return 1; |
75 | } | |
76 | ||
77 | static int parse_options(int argc, char *argv[]) | |
78 | { | |
79 | int c, index = 1; | |
80 | ||
ef0e4210 | 81 | while ((c = getopt(argc, argv, "admz")) != -1) { |
d07a80dc | 82 | switch (c) { |
ef0e4210 JA |
83 | case 'a': |
84 | do_ascii = 1; | |
85 | index++; | |
86 | break; | |
d07a80dc JA |
87 | case 'd': |
88 | do_dump = 1; | |
89 | index++; | |
90 | break; | |
ef0e4210 JA |
91 | case 'm': |
92 | splice_flags |= SPLICE_F_MOVE; | |
93 | index++; | |
94 | break; | |
95 | case 'z': | |
96 | do_zeromap = 1; | |
97 | index++; | |
98 | break; | |
d07a80dc JA |
99 | default: |
100 | return -1; | |
101 | } | |
102 | } | |
103 | ||
104 | return index; | |
105 | } | |
106 | ||
107 | static void hexdump(unsigned char *buf, int len) | |
108 | { | |
109 | int i; | |
110 | ||
111 | for (i = 0; i < len; i++) | |
112 | printf("%02x", buf[i]); | |
ef0e4210 JA |
113 | } |
114 | ||
115 | static void asciidump(unsigned char *buf, int len) | |
116 | { | |
117 | int i; | |
118 | ||
119 | for (i = 0; i < len; i++) | |
120 | printf("%c", buf[i]); | |
d07a80dc JA |
121 | } |
122 | ||
123 | int main(int argc, char *argv[]) | |
124 | { | |
c972eeeb | 125 | void *buf; |
d07a80dc JA |
126 | int ret; |
127 | ||
128 | if (parse_options(argc, argv) < 0) | |
129 | return usage(argv[0]); | |
130 | ||
131 | if (check_input_pipe()) | |
132 | return usage(argv[0]); | |
133 | ||
1e404f5c JA |
134 | if (do_zeromap && !(splice_flags & SPLICE_F_MOVE)) { |
135 | fprintf(stderr, "zero map only valid for -m(ove)\n"); | |
136 | return usage(argv[0]); | |
137 | } | |
138 | ||
ef0e4210 JA |
139 | if (!do_zeromap) { |
140 | buf = malloc(4096); | |
141 | memset(buf, 0, 4096); | |
142 | } else | |
143 | buf = NULL; | |
d07a80dc | 144 | |
ef0e4210 | 145 | ret = do_vmsplice(STDIN_FILENO, &buf, 4096); |
d07a80dc JA |
146 | if (ret < 0) |
147 | return 1; | |
148 | ||
d07a80dc JA |
149 | if (do_dump) |
150 | hexdump(buf, ret); | |
ef0e4210 JA |
151 | if (do_ascii) |
152 | asciidump(buf, ret); | |
d07a80dc | 153 | |
ef0e4210 JA |
154 | if (splice_flags & SPLICE_F_MOVE) { |
155 | ret = do_vmsplice_unmap(STDIN_FILENO, buf, 4096); | |
156 | if (ret < 0) | |
157 | perror("vmsplice"); | |
158 | } | |
159 | ||
160 | return ret; | |
d07a80dc | 161 | } |