From 1bb734a44952a51285057409ba7b1c3e7a162cea Mon Sep 17 00:00:00 2001 From: Michal Sekletar Date: Thu, 2 Aug 2018 13:16:49 +0200 Subject: [PATCH] Revert "udev: remove WAIT_FOR key" This reverts commit f2b8052fb648b788936dd3e85be6a9aca90fbb2f. Resolves: #1523213 --- man/udev.xml | 9 +++++++ src/udev/udev-rules.c | 50 +++++++++++++++++++++++++++++++++++++++ test/rule-syntax-check.py | 2 +- 3 files changed, 60 insertions(+), 1 deletion(-) diff --git a/man/udev.xml b/man/udev.xml index 15e6d8eae1..bdf901a8f0 100644 --- a/man/udev.xml +++ b/man/udev.xml @@ -515,6 +515,15 @@ + + WAIT_FOR + + Wait for a file to become available or until a timeout of + 10 seconds expires. The path is relative to the sysfs device; + if no path is specified, this waits for an attribute to appear. + + + OPTIONS diff --git a/src/udev/udev-rules.c b/src/udev/udev-rules.c index f029395884..58af863f3d 100644 --- a/src/udev/udev-rules.c +++ b/src/udev/udev-rules.c @@ -676,6 +676,41 @@ static int import_parent_into_properties(struct udev_device *dev, const char *fi return 0; } +#define WAIT_LOOP_PER_SECOND 50 +static int wait_for_file(struct udev_device *dev, const char *file, int timeout) { + char filepath[UTIL_PATH_SIZE]; + char devicepath[UTIL_PATH_SIZE]; + struct stat stats; + int loop = timeout * WAIT_LOOP_PER_SECOND; + + /* a relative path is a device attribute */ + devicepath[0] = '\0'; + if (file[0] != '/') { + strscpyl(devicepath, sizeof(devicepath), udev_device_get_syspath(dev), NULL); + strscpyl(filepath, sizeof(filepath), devicepath, "/", file, NULL); + file = filepath; + } + + while (--loop) { + const struct timespec duration = { 0, 1000 * 1000 * 1000 / WAIT_LOOP_PER_SECOND }; + + /* lookup file */ + if (stat(file, &stats) == 0) { + log_debug("file '%s' appeared after %i loops", file, (timeout * WAIT_LOOP_PER_SECOND) - loop-1); + return 0; + } + /* make sure, the device did not disappear in the meantime */ + if (devicepath[0] != '\0' && stat(devicepath, &stats) != 0) { + log_debug("device disappeared while waiting for '%s'", file); + return -2; + } + log_debug("wait for '%s' for %i mseconds", file, 1000 / WAIT_LOOP_PER_SECOND); + nanosleep(&duration, NULL); + } + log_debug("waiting for '%s' failed", file); + return -1; +} + static void attr_subst_subdir(char *attr, size_t len) { const char *pos, *tail, *path; _cleanup_closedir_ DIR *dir = NULL; @@ -1284,7 +1319,12 @@ static void add_rule(struct udev_rules *rules, char *line, rule_add_key(&rule_tmp, TK_A_RUN_PROGRAM, op, value, &cmd); } else LOG_RULE_ERROR("ignoring unknown %s{} type '%s'", "RUN", attr); + } else if (streq(key, "WAIT_FOR") || streq(key, "WAIT_FOR_SYSFS")) { + if (op == OP_REMOVE) + LOG_AND_RETURN("invalid %s operation", key); + rule_add_key(&rule_tmp, TK_M_WAITFOR, 0, value, NULL); + continue; } else if (streq(key, "LABEL")) { if (op == OP_REMOVE) LOG_AND_RETURN("invalid %s operation", key); @@ -1838,6 +1878,16 @@ void udev_rules_apply_to_event(struct udev_rules *rules, if (match_key(rules, cur, udev_device_get_driver(event->dev)) != 0) goto nomatch; break; + case TK_M_WAITFOR: { + char filename[UTIL_PATH_SIZE]; + int found; + + udev_event_apply_format(event, rules_str(rules, cur->key.value_off), filename, sizeof(filename), false); + found = (wait_for_file(event->dev, filename, 10) == 0); + if (!found && (cur->key.op != OP_NOMATCH)) + goto nomatch; + break; + } case TK_M_ATTR: if (match_attr(rules, event->dev, event, cur) != 0) goto nomatch; diff --git a/test/rule-syntax-check.py b/test/rule-syntax-check.py index dfb06d9ed9..706d93632e 100755 --- a/test/rule-syntax-check.py +++ b/test/rule-syntax-check.py @@ -18,7 +18,7 @@ if not rules_files: quoted_string_re = r'"(?:[^\\"]|\\.)*"' no_args_tests = re.compile(r'(ACTION|DEVPATH|KERNELS?|NAME|SYMLINK|SUBSYSTEMS?|DRIVERS?|TAG|PROGRAM|RESULT|TEST)\s*(?:=|!)=\s*' + quoted_string_re + '$') args_tests = re.compile(r'(ATTRS?|ENV|TEST){([a-zA-Z0-9/_.*%-]+)}\s*(?:=|!)=\s*' + quoted_string_re + '$') -no_args_assign = re.compile(r'(NAME|SYMLINK|OWNER|GROUP|MODE|TAG|RUN|LABEL|GOTO|OPTIONS|IMPORT)\s*(?:\+=|:=|=)\s*' + quoted_string_re + '$') +no_args_assign = re.compile(r'(NAME|SYMLINK|OWNER|GROUP|MODE|TAG|RUN|LABEL|GOTO|WAIT_FOR|OPTIONS|IMPORT)\s*(?:\+=|:=|=)\s*' + quoted_string_re + '$') args_assign = re.compile(r'(ATTR|ENV|IMPORT|RUN){([a-zA-Z0-9/_.*%-]+)}\s*(=|\+=)\s*' + quoted_string_re + '$') # Find comma-separated groups, but allow commas that are inside quoted strings. # Using quoted_string_re + '?' so that strings missing the last double quote