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 | 19 | static int splice_flags; |
fe3a0890 | 20 | static unsigned int splice_size = SPLICE_SIZE; |
d07a80dc | 21 | |
ef0e4210 JA |
22 | static int do_vmsplice_unmap(int fd, unsigned char *buf, int len) |
23 | { | |
24 | struct iovec iov = { | |
25 | .iov_base = buf, | |
26 | .iov_len = len, | |
27 | }; | |
28 | ||
29 | return svmsplice(fd, &iov, 1, SPLICE_F_UNMAP); | |
30 | } | |
31 | ||
c972eeeb | 32 | static int do_vmsplice(int fd, void **buf, int len) |
d07a80dc JA |
33 | { |
34 | struct pollfd pfd = { .fd = fd, .events = POLLIN, }; | |
c972eeeb JA |
35 | struct iovec iov = { |
36 | .iov_base = *buf, | |
37 | .iov_len = len, | |
38 | }; | |
d07a80dc | 39 | int written; |
c972eeeb | 40 | int ret = 0; |
d07a80dc JA |
41 | |
42 | while (len) { | |
43 | /* | |
44 | * in a real app you'd be more clever with poll of course, | |
45 | * here we are basically just blocking on output room and | |
46 | * not using the free time for anything interesting. | |
47 | */ | |
48 | if (poll(&pfd, 1, -1) < 0) | |
49 | return error("poll"); | |
50 | ||
13b72067 | 51 | written = svmsplice(fd, &iov, 1, splice_flags); |
c972eeeb JA |
52 | |
53 | if (!ret) | |
54 | *buf = iov.iov_base; | |
d07a80dc JA |
55 | |
56 | if (written < 0) | |
57 | return error("vmsplice"); | |
58 | else if (!written) | |
59 | break; | |
60 | ||
61 | len -= written; | |
62 | ret += written; | |
63 | if (len) { | |
64 | iov.iov_len -= written; | |
65 | iov.iov_base += written; | |
66 | } | |
67 | } | |
68 | ||
69 | return ret; | |
70 | } | |
71 | ||
72 | static int usage(char *name) | |
73 | { | |
fe3a0890 | 74 | fprintf(stderr, "| %s [-s(ize)] [-d(ump)] [-a(ascii)] [-m(ap)] [-z(eromap)] [-n non-block]\n", name); |
d07a80dc JA |
75 | return 1; |
76 | } | |
77 | ||
78 | static int parse_options(int argc, char *argv[]) | |
79 | { | |
80 | int c, index = 1; | |
81 | ||
fe3a0890 | 82 | while ((c = getopt(argc, argv, "admzs:n")) != -1) { |
d07a80dc | 83 | switch (c) { |
ef0e4210 JA |
84 | case 'a': |
85 | do_ascii = 1; | |
86 | index++; | |
87 | break; | |
d07a80dc JA |
88 | case 'd': |
89 | do_dump = 1; | |
90 | index++; | |
91 | break; | |
ef0e4210 JA |
92 | case 'm': |
93 | splice_flags |= SPLICE_F_MOVE; | |
94 | index++; | |
95 | break; | |
96 | case 'z': | |
97 | do_zeromap = 1; | |
98 | index++; | |
99 | break; | |
fe3a0890 JA |
100 | case 's': |
101 | splice_size = atoi(optarg); | |
102 | index++; | |
103 | break; | |
104 | case 'n': | |
105 | splice_flags |= SPLICE_F_NONBLOCK; | |
106 | index++; | |
107 | break; | |
d07a80dc JA |
108 | default: |
109 | return -1; | |
110 | } | |
111 | } | |
112 | ||
fe3a0890 JA |
113 | if (do_zeromap && !(splice_flags & SPLICE_F_MOVE)) { |
114 | fprintf(stderr, "zero map only valid for -m(ove)\n"); | |
115 | return -1; | |
116 | } | |
117 | ||
d07a80dc JA |
118 | return index; |
119 | } | |
120 | ||
121 | static void hexdump(unsigned char *buf, int len) | |
122 | { | |
123 | int i; | |
124 | ||
125 | for (i = 0; i < len; i++) | |
126 | printf("%02x", buf[i]); | |
ef0e4210 JA |
127 | } |
128 | ||
129 | static void asciidump(unsigned char *buf, int len) | |
130 | { | |
131 | int i; | |
132 | ||
133 | for (i = 0; i < len; i++) | |
134 | printf("%c", buf[i]); | |
d07a80dc JA |
135 | } |
136 | ||
137 | int main(int argc, char *argv[]) | |
138 | { | |
c972eeeb | 139 | void *buf; |
d07a80dc JA |
140 | int ret; |
141 | ||
142 | if (parse_options(argc, argv) < 0) | |
143 | return usage(argv[0]); | |
144 | ||
145 | if (check_input_pipe()) | |
146 | return usage(argv[0]); | |
147 | ||
ef0e4210 | 148 | if (!do_zeromap) { |
fe3a0890 JA |
149 | buf = malloc(splice_size); |
150 | memset(buf, 0, splice_size); | |
ef0e4210 JA |
151 | } else |
152 | buf = NULL; | |
d07a80dc | 153 | |
fe3a0890 | 154 | ret = do_vmsplice(STDIN_FILENO, &buf, splice_size); |
d07a80dc JA |
155 | if (ret < 0) |
156 | return 1; | |
fe3a0890 JA |
157 | else if (!ret) |
158 | return 0; | |
d07a80dc | 159 | |
d07a80dc JA |
160 | if (do_dump) |
161 | hexdump(buf, ret); | |
ef0e4210 JA |
162 | if (do_ascii) |
163 | asciidump(buf, ret); | |
d07a80dc | 164 | |
ef0e4210 | 165 | if (splice_flags & SPLICE_F_MOVE) { |
fe3a0890 | 166 | ret = do_vmsplice_unmap(STDIN_FILENO, buf, ret); |
ef0e4210 JA |
167 | if (ret < 0) |
168 | perror("vmsplice"); | |
169 | } | |
170 | ||
171 | return ret; | |
d07a80dc | 172 | } |