1 /*
2 * Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the
6 * Free Software Foundation version 2 of the License.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
16 *
17 */
18
19 #define MY_MAX(a,b) ((a) > (b) ? (a) : (b))
20
21 #define READ_END 0
22 #define WRITE_END 1
23
24 static
25 int run_program1(struct space *space,
26 const char *command0, char *result,
27 size_t ressize, size_t *reslen, int log);
28
29 static
run_program0(struct space * space,const char * command0,char * result,size_t ressize,size_t * reslen,int log)30 int run_program0(struct space *space,
31 const char *command0, char *result,
32 size_t ressize, size_t *reslen, int log)
33 {
34 int retval = 0;
35 int status;
36 int outpipe[2] = {-1, -1};
37 int errpipe[2] = {-1, -1};
38 pid_t pid;
39 char arg[PATH_SIZE];
40 char program[PATH_SIZE];
41 char *argv[(sizeof(arg) / 2) + 1];
42 int devnull;
43 int i;
44
45 /* build argv from comand */
46 strlcpy(arg, command0, sizeof(arg));
47 i = 0;
48 if (strchr(arg, ' ') != NULL) {
49 char *pos = arg;
50
51 while (pos != NULL) {
52 if (pos[0] == '\'') {
53 /* don't separate if in apostrophes */
54 pos++;
55 argv[i] = strsep(&pos, "\'");
56 while (pos != NULL && pos[0] == ' ')
57 pos++;
58 } else {
59 argv[i] = strsep(&pos, " ");
60 }
61 dbg("arg[%i] '%s'", i, argv[i]);
62 i++;
63 }
64 argv[i] = NULL;
65 } else {
66 argv[0] = arg;
67 argv[1] = NULL;
68 }
69 info("'%s'", command0);
70
71 /* prepare pipes from child to parent */
72 if (result || log) {
73 if (pipe(outpipe) != 0) {
74 Perror(space, "pipe failed: %s", strerror(errno));
75 return -1;
76 }
77 }
78 if (log) {
79 if (pipe(errpipe) != 0) {
80 Perror(space, "pipe failed: %s", strerror(errno));
81 return -1;
82 }
83 }
84
85 /* allow programs in /lib/alsa called without the path */
86 if (strchr(argv[0], '/') == NULL) {
87 strlcpy(program, "/lib/alsa/", sizeof(program));
88 strlcat(program, argv[0], sizeof(program));
89 argv[0] = program;
90 }
91
92 pid = fork();
93 switch(pid) {
94 case 0:
95 /* child closes parent ends of pipes */
96 if (outpipe[READ_END] > 0)
97 close(outpipe[READ_END]);
98 if (errpipe[READ_END] > 0)
99 close(errpipe[READ_END]);
100
101 /* discard child output or connect to pipe */
102 devnull = open("/dev/null", O_RDWR);
103 if (devnull > 0) {
104 dup2(devnull, STDIN_FILENO);
105 if (outpipe[WRITE_END] < 0)
106 dup2(devnull, STDOUT_FILENO);
107 if (errpipe[WRITE_END] < 0)
108 dup2(devnull, STDERR_FILENO);
109 close(devnull);
110 } else
111 Perror(space, "open /dev/null failed: %s", strerror(errno));
112 if (outpipe[WRITE_END] > 0) {
113 dup2(outpipe[WRITE_END], STDOUT_FILENO);
114 close(outpipe[WRITE_END]);
115 }
116 if (errpipe[WRITE_END] > 0) {
117 dup2(errpipe[WRITE_END], STDERR_FILENO);
118 close(errpipe[WRITE_END]);
119 }
120 execv(argv[0], argv);
121
122 /* we should never reach this */
123 Perror(space, "exec of program '%s' failed", argv[0]);
124 _exit(1);
125 case -1:
126 Perror(space, "fork of '%s' failed: %s", argv[0], strerror(errno));
127 return -1;
128 default:
129 /* read from child if requested */
130 if (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) {
131 ssize_t count;
132 size_t respos = 0;
133
134 /* parent closes child ends of pipes */
135 if (outpipe[WRITE_END] > 0)
136 close(outpipe[WRITE_END]);
137 if (errpipe[WRITE_END] > 0)
138 close(errpipe[WRITE_END]);
139
140 /* read child output */
141 while (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) {
142 int fdcount;
143 fd_set readfds;
144
145 FD_ZERO(&readfds);
146 if (outpipe[READ_END] > 0)
147 FD_SET(outpipe[READ_END], &readfds);
148 if (errpipe[READ_END] > 0)
149 FD_SET(errpipe[READ_END], &readfds);
150 fdcount = select(MY_MAX(outpipe[READ_END], errpipe[READ_END])+1, &readfds, NULL, NULL, NULL);
151 if (fdcount < 0) {
152 if (errno == EINTR)
153 continue;
154 retval = -1;
155 break;
156 }
157
158 /* get stdout */
159 if (outpipe[READ_END] > 0 && FD_ISSET(outpipe[READ_END], &readfds)) {
160 char inbuf[1024];
161 char *pos;
162 char *line;
163
164 count = read(outpipe[READ_END], inbuf, sizeof(inbuf)-1);
165 if (count <= 0) {
166 close(outpipe[READ_END]);
167 outpipe[READ_END] = -1;
168 if (count < 0) {
169 Perror(space, "stdin read failed: %s", strerror(errno));
170 retval = -1;
171 }
172 continue;
173 }
174 inbuf[count] = '\0';
175
176 /* store result for rule processing */
177 if (result) {
178 if (respos + count < ressize) {
179 memcpy(&result[respos], inbuf, count);
180 respos += count;
181 } else {
182 Perror(space, "ressize %ld too short", (long)ressize);
183 retval = -1;
184 }
185 }
186 pos = inbuf;
187 while ((line = strsep(&pos, "\n")))
188 if (pos || line[0] != '\0')
189 info("'%s' (stdout) '%s'", argv[0], line);
190 }
191
192 /* get stderr */
193 if (errpipe[READ_END] > 0 && FD_ISSET(errpipe[READ_END], &readfds)) {
194 char errbuf[1024];
195 char *pos;
196 char *line;
197
198 count = read(errpipe[READ_END], errbuf, sizeof(errbuf)-1);
199 if (count <= 0) {
200 close(errpipe[READ_END]);
201 errpipe[READ_END] = -1;
202 if (count < 0)
203 Perror(space, "stderr read failed: %s", strerror(errno));
204 continue;
205 }
206 errbuf[count] = '\0';
207 pos = errbuf;
208 while ((line = strsep(&pos, "\n")))
209 if (pos || line[0] != '\0')
210 info("'%s' (stderr) '%s'", argv[0], line);
211 }
212 }
213 if (outpipe[READ_END] > 0)
214 close(outpipe[READ_END]);
215 if (errpipe[READ_END] > 0)
216 close(errpipe[READ_END]);
217
218 /* return the childs stdout string */
219 if (result) {
220 result[respos] = '\0';
221 dbg("result='%s'", result);
222 if (reslen)
223 *reslen = respos;
224 }
225 }
226 waitpid(pid, &status, 0);
227 if (WIFEXITED(status)) {
228 info("'%s' returned with status %i", argv[0], WEXITSTATUS(status));
229 if (WEXITSTATUS(status) != 0)
230 retval = -1;
231 } else {
232 Perror(space, "'%s' abnormal exit", argv[0]);
233 retval = -1;
234 }
235 }
236
237 return retval;
238 }
239
240 static
run_program(struct space * space,const char * command0,char * result,size_t ressize,size_t * reslen,int log)241 int run_program(struct space *space, const char *command0, char *result,
242 size_t ressize, size_t *reslen, int log)
243 {
244 if (command0[0] == '_' && command0[1] == '_')
245 return run_program1(space, command0, result, ressize, reslen, log);
246 return run_program0(space, command0, result, ressize, reslen, log);
247 }
248