From: Lennart Poettering Date: Tue, 28 Sep 2010 00:34:02 +0000 (+0200) Subject: tempfiles: add little utility for creating volatile files/dirs in tmpfs hierarchies X-Git-Tag: v11~58 X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=5008d5815a6223f01c9fc4c803ec6ec18c8f4e54 tempfiles: add little utility for creating volatile files/dirs in tmpfs hierarchies --- diff --git a/.gitignore b/.gitignore index b5fc8d72b..453635638 100644 --- a/.gitignore +++ b/.gitignore @@ -1,3 +1,4 @@ +systemd-tempfiles systemd-readahead-collect systemd-readahead-replay systemd-reply-password diff --git a/Makefile.am b/Makefile.am index 70a6c190f..342b2b241 100644 --- a/Makefile.am +++ b/Makefile.am @@ -94,7 +94,8 @@ rootlibexec_PROGRAMS = \ systemd-vconsole-setup \ systemd-reply-password \ systemd-readahead-collect \ - systemd-readahead-replay + systemd-readahead-replay \ + systemd-tempfiles noinst_PROGRAMS = \ test-engine \ @@ -620,6 +621,15 @@ systemd_modules_load_SOURCES = \ systemd_modules_load_CFLAGS = \ $(AM_CFLAGS) +systemd_tempfiles_LDADD = \ + libsystemd-basic.la + +systemd_tempfiles_SOURCES = \ + src/tempfiles.c + +systemd_tempfiles_CFLAGS = \ + $(AM_CFLAGS) + systemd_modules_load_LDADD = \ libsystemd-basic.la diff --git a/fixme b/fixme index 68a64890e..f66f07a03 100644 --- a/fixme +++ b/fixme @@ -89,19 +89,17 @@ * ask-password tty timeout -* readahead() vs. fadvise() vs. ioprio - * properly handle multiple inotify events per read() in path.c and util.c -* tmpwatch: what does "-umc" actually mean? - * tmpwatch: lower ioprio * readahead: btrfs/LVM SSD detection * LSB provides should only create targets, never aliases -* d /var/run/screen 0755 root utmp +* s/tempfiles/volatile-files/ + +* use .conf suffix for locale/vconsole/... External: diff --git a/src/tempfiles.c b/src/tempfiles.c new file mode 100644 index 000000000..80e424f7b --- /dev/null +++ b/src/tempfiles.c @@ -0,0 +1,307 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2010 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with systemd; If not, see . +***/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "log.h" +#include "util.h" +#include "strv.h" +#include "label.h" + +/* This reads all files listed in /etc/tempfiles.d/?*.conf and creates + * them in the file system. This is intended to be used to create + * properly owned directories beneath /tmp, /var/tmp, /var/run and + * /var/lock which are volatile and hence need to be recreated on + * bootup. */ + +static void process_line(const char *fname, unsigned line, const char *buffer, const char *prefix) { + char type; + char *path = NULL; + unsigned mode; + char *user = NULL, *group = NULL; + uid_t uid; + gid_t gid; + bool uid_set = false, gid_set = false; + int n, fd = -1; + + assert(fname); + assert(line >= 1); + assert(buffer); + + if ((n = sscanf(buffer, + "%c " + "%ms " + "%o " + "%ms " + "%ms ", + &type, + &path, + &mode, + &user, + &group)) < 2) { + log_error("[%s:%u] Syntax error.", fname, line); + goto finish; + } + + if (type != 'f' && type != 'd') { + log_error("[%s:%u] Unknown file type '%c'.", fname, line, type); + goto finish; + } + + if (prefix && !path_startswith(path, prefix)) + goto finish; + + if (user && !streq(user, "-")) { + unsigned long lu; + struct passwd *p; + + if (streq(user, "root") || streq(user, "0")) + uid = 0; + else if (safe_atolu(user, &lu) >= 0) + uid = (uid_t) lu; + else if ((p = getpwnam(user))) + uid = p->pw_uid; + else { + log_error("[%s:%u] Unknown user '%s'.", fname, line, user); + goto finish; + } + + uid_set = true; + } + + if (group && !streq(group, "-")) { + unsigned long lu; + struct group *g; + + if (streq(group, "root") || streq(group, "0")) + gid = 0; + else if (safe_atolu(group, &lu) >= 0) + gid = (gid_t) lu; + else if ((g = getgrnam(group))) + gid = g->gr_gid; + else { + log_error("[%s:%u] Unknown group '%s'.", fname, line, group); + goto finish; + } + + gid_set = true; + } + + if (n < 3) + mode = type == 'f' ? 0644 : 0755; + + if (type == 'f') { + mode_t u; + struct stat st; + + u = umask(0); + fd = open(path, O_CREAT|O_NDELAY|O_CLOEXEC|O_WRONLY|O_NOCTTY|O_NOFOLLOW, mode); + umask(u); + + if (fd < 0) { + log_error("Failed to create file %s: %m", path); + goto finish; + } + + if (fstat(fd, &st) < 0) { + log_error("stat(%s) failed: %m", path); + goto finish; + } + + if (!S_ISREG(st.st_mode)) { + log_error("%s is not a file.", path); + goto finish; + } + + if (fchmod(fd, mode) < 0) { + log_error("chmod(%s) failed: %m", path); + goto finish; + } + + if (uid_set || gid_set) { + + if (fchown(fd, + uid_set ? uid : (uid_t) -1, + gid_set ? gid : (gid_t) -1) < 0) { + log_error("chown(%s) failed: %m", path); + goto finish; + } + } + + } else if (type == 'd') { + mode_t u; + int r; + struct stat st; + + u = umask(0); + r = mkdir(path, mode); + umask(u); + + if (r < 0 && errno != EEXIST) { + log_error("Failed to create directory %s: %m", path); + goto finish; + } + + if (stat(path, &st) < 0) { + log_error("stat(%s) failed: %m", path); + goto finish; + } + + if (!S_ISDIR(st.st_mode)) { + log_error("%s is not a directory.", path); + goto finish; + } + + if (chmod(path, mode) < 0) { + log_error("chmod(%s) failed: %m", path); + goto finish; + } + + if (uid_set || gid_set) { + + if (chown(path, + uid_set ? uid : (uid_t) -1, + gid_set ? gid : (gid_t) -1) < 0) { + log_error("chown(%s) failed: %m", path); + goto finish; + } + } + } + + label_fix(path); + + log_debug("%s created successfully.", path); + +finish: + free(path); + free(user); + free(group); + + if (fd >= 0) + close_nointr_nofail(fd); +} + +static int scandir_filter(const struct dirent *d) { + assert(d); + + if (ignore_file(d->d_name)) + return 0; + + if (d->d_type != DT_REG && + d->d_type != DT_LNK) + return 0; + + return endswith(d->d_name, ".conf"); +} + +int main(int argc, char *argv[]) { + struct dirent **de = NULL; + int r = EXIT_FAILURE, n, i; + const char *prefix = NULL; + + if (argc > 2) { + log_error("This program takes no more than one argument."); + return EXIT_FAILURE; + } else if (argc > 1) + prefix = argv[1]; + else + prefix = "/"; + + log_set_target(LOG_TARGET_SYSLOG_OR_KMSG); + log_parse_environment(); + log_open(); + + label_init(); + + if ((n = scandir("/etc/tempfiles.d/", &de, scandir_filter, alphasort)) < 0) { + + if (errno == ENOENT) + r = EXIT_SUCCESS; + else + log_error("Failed to enumerate /etc/tempfiles.d/ files: %m"); + + goto finish; + } + + r = EXIT_SUCCESS; + + for (i = 0; i < n; i++) { + int k; + char *fn; + FILE *f; + unsigned j; + + k = asprintf(&fn, "/etc/tempfiles.d/%s", de[i]->d_name); + free(de[i]); + + if (k < 0) { + log_error("Failed to allocate file name."); + r = EXIT_FAILURE; + continue; + } + + f = fopen(fn, "re"); + free(fn); + + if (!f) { + log_error("Failed to open %s: %m", fn); + r = EXIT_FAILURE; + continue; + } + + j = 0; + for (;;) { + char line[LINE_MAX], *l; + + if (!(fgets(line, sizeof(line), f))) + break; + + j++; + + l = strstrip(line); + if (*l == '#' || *l == 0) + continue; + + process_line(de[i]->d_name, j, l, prefix); + } + + if (ferror(f)) { + r = EXIT_FAILURE; + log_error("Failed to read from file: %m"); + } + + fclose(f); + } + + free(de); + +finish: + + return r; +}