2 * Collect variables across events.
4 * usage: collect [--add|--remove] <checkpoint> <id> <idlist>
6 * Adds ID <id> to the list governed by <checkpoint>.
7 * <id> must be part of the ID list <idlist>.
8 * If all IDs given by <idlist> are listed (ie collect has been
9 * invoked for each ID in <idlist>) collect returns 0, the
10 * number of missing IDs otherwise.
11 * A negative number is returned on error.
13 * Copyright(C) 2007, Hannes Reinecke <hare@suse.de>
15 * This program is free software: you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation, either version 2 of the License, or
18 * (at your option) any later version.
27 #include "libudev-private.h"
31 #define UDEV_ALARM_TIMEOUT 180
40 struct udev_list_node node;
42 enum collect_state state;
45 static struct udev_list_node bunch;
48 /* This can increase dynamically */
49 static size_t bufsize = BUFSIZE;
51 static inline struct _mate *node_to_mate(struct udev_list_node *node)
53 return container_of(node, struct _mate, node);
56 noreturn static void sig_alrm(int signo)
61 static void usage(void)
63 printf("%s [options] <checkpoint> <id> <idlist>\n\n"
64 "Collect variables across events.\n\n"
65 " -h --help Print this message\n"
66 " -a --add Add ID <id> to the list <idlist>\n"
67 " -r --remove Remove ID <id> from the list <idlist>\n"
68 " -d --debug Debug to stderr\n\n"
69 " Adds ID <id> to the list governed by <checkpoint>.\n"
70 " <id> must be part of the list <idlist>.\n"
71 " If all IDs given by <idlist> are listed (ie collect has been\n"
72 " invoked for each ID in <idlist>) collect returns 0, the\n"
73 " number of missing IDs otherwise.\n"
74 " On error a negative number is returned.\n\n"
75 , program_invocation_short_name);
81 * Prepares the database file
83 static int prepare(char *dir, char *filename)
89 if (r < 0 && errno != EEXIST)
92 snprintf(buf, sizeof(buf), "%s/%s", dir, filename);
94 fd = open(buf,O_RDWR|O_CREAT|O_CLOEXEC, S_IRUSR|S_IWUSR);
96 fprintf(stderr, "Cannot open %s: %m\n", buf);
98 if (lockf(fd,F_TLOCK,0) < 0) {
100 fprintf(stderr, "Lock taken, wait for %d seconds\n", UDEV_ALARM_TIMEOUT);
101 if (errno == EAGAIN || errno == EACCES) {
102 alarm(UDEV_ALARM_TIMEOUT);
103 lockf(fd, F_LOCK, 0);
105 fprintf(stderr, "Acquired lock on %s\n", buf);
108 fprintf(stderr, "Could not get lock on %s: %m\n", buf);
116 * Read checkpoint file
118 * Tricky reading this. We allocate a buffer twice as large
119 * as we're going to read. Then we read into the upper half
120 * of that buffer and start parsing.
121 * Once we do _not_ find end-of-work terminator (whitespace
122 * character) we move the upper half to the lower half,
123 * adjust the read pointer and read the next bit.
124 * Quite clever methinks :-)
125 * I should become a programmer ...
127 * Yes, one could have used fgets() for this. But then we'd
128 * have to use freopen etc which I found quite tedious.
130 static int checkout(int fd)
133 char *buf, *ptr, *word = NULL;
138 buf = malloc(bufsize + 1);
141 memset(buf, ' ', bufsize);
145 while ((read(fd, buf + len, len)) > 0) {
146 while (ptr && *ptr) {
148 ptr = strpbrk(word," \n\t\r");
149 if (!ptr && word < (buf + len)) {
150 bufsize = bufsize << 1;
152 fprintf(stderr, "ID overflow, restarting with size %zu\n", bufsize);
154 lseek(fd, 0, SEEK_SET);
164 fprintf(stderr, "Found word %s\n", word);
165 him = malloc(sizeof (struct _mate));
170 him->name = strdup(word);
176 him->state = STATE_OLD;
177 udev_list_node_append(&him->node, &bunch);
181 memcpy(buf, buf + len, len);
182 memset(buf + len, ' ', len);
198 * Adds a new ID 'us' to the internal list,
199 * marks it as confirmed.
201 static void invite(char *us)
203 struct udev_list_node *him_node;
204 struct _mate *who = NULL;
207 fprintf(stderr, "Adding ID '%s'\n", us);
209 udev_list_node_foreach(him_node, &bunch) {
210 struct _mate *him = node_to_mate(him_node);
212 if (streq(him->name, us)) {
213 him->state = STATE_CONFIRMED;
218 fprintf(stderr, "ID '%s' not in database\n", us);
225 * Marks the ID 'us' as invalid,
226 * causing it to be removed when the
227 * list is written out.
229 static void reject(char *us)
231 struct udev_list_node *him_node;
232 struct _mate *who = NULL;
235 fprintf(stderr, "Removing ID '%s'\n", us);
237 udev_list_node_foreach(him_node, &bunch) {
238 struct _mate *him = node_to_mate(him_node);
240 if (streq(him->name, us)) {
241 him->state = STATE_NONE;
246 fprintf(stderr, "ID '%s' not in database\n", us);
252 * Remove all IDs in the internal list which are not part
253 * of the list passed via the command line.
255 static void kickout(void)
257 struct udev_list_node *him_node;
258 struct udev_list_node *tmp;
260 udev_list_node_foreach_safe(him_node, tmp, &bunch) {
261 struct _mate *him = node_to_mate(him_node);
263 if (him->state == STATE_OLD) {
264 udev_list_node_remove(&him->node);
274 * Counts all missing IDs in the internal list.
276 static int missing(int fd)
280 struct udev_list_node *him_node;
282 buf = malloc(bufsize);
286 udev_list_node_foreach(him_node, &bunch) {
287 struct _mate *him = node_to_mate(him_node);
289 if (him->state == STATE_NONE) {
292 while (strlen(him->name)+1 >= bufsize) {
295 bufsize = bufsize << 1;
296 tmpbuf = realloc(buf, bufsize);
303 snprintf(buf, strlen(him->name)+2, "%s ", him->name);
304 if (write(fd, buf, strlen(buf)) < 0) {
318 * Prints out the status of the internal list.
320 static void everybody(void)
322 struct udev_list_node *him_node;
323 const char *state = "";
325 udev_list_node_foreach(him_node, &bunch) {
326 struct _mate *him = node_to_mate(him_node);
328 switch (him->state) {
335 case STATE_CONFIRMED:
339 fprintf(stderr, "ID: %s=%s\n", him->name, state);
343 int main(int argc, char **argv)
346 static const struct option options[] = {
347 { "add", no_argument, NULL, 'a' },
348 { "remove", no_argument, NULL, 'r' },
349 { "debug", no_argument, NULL, 'd' },
350 { "help", no_argument, NULL, 'h' },
354 char *checkpoint, *us;
357 int ret = EXIT_SUCCESS;
359 char tmpdir[UTIL_PATH_SIZE];
370 option = getopt_long(argc, argv, "ardh", options, NULL);
394 if (argi + 2 > argc) {
395 printf("Missing parameter(s)\n");
399 checkpoint = argv[argi++];
402 if (signal(SIGALRM, sig_alrm) == SIG_ERR) {
403 fprintf(stderr, "Cannot set SIGALRM: %m\n");
408 udev_list_node_init(&bunch);
411 fprintf(stderr, "Using checkpoint '%s'\n", checkpoint);
413 strscpyl(tmpdir, sizeof(tmpdir), "/run/udev/collect", NULL);
414 fd = prepare(tmpdir, checkpoint);
420 if (checkout(fd) < 0) {
425 for (i = argi; i < argc; i++) {
426 struct udev_list_node *him_node;
430 udev_list_node_foreach(him_node, &bunch) {
431 struct _mate *him = node_to_mate(him_node);
433 if (streq(him->name, argv[i]))
440 fprintf(stderr, "ID %s: not in database\n", argv[i]);
441 him = new(struct _mate, 1);
447 him->name = strdup(argv[i]);
454 him->state = STATE_NONE;
455 udev_list_node_append(&him->node, &bunch);
458 fprintf(stderr, "ID %s: found in database\n", argv[i]);
459 who->state = STATE_CONFIRMED;
470 fprintf(stderr, "Prune lists\n");
474 lseek(fd, 0, SEEK_SET);
478 lockf(fd, F_ULOCK, 0);
484 printf("COLLECT_%s=%d\n", checkpoint, ret);