From 1c41caca9ff73085513b988edbb341e076244298 Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Mon, 6 Jul 2015 19:19:25 -0400 Subject: [PATCH] fileio: consolidate write_string_file*() Merge write_string_file(), write_string_file_no_create() and write_string_file_atomic() into write_string_file() and provide a flags mask that allows combinations of atomic writing, newline appending and automatic file creation. Change all users accordingly. --- src/login/logind-dbus.c | 4 +-- src/shared/capability.c | 2 +- src/shared/cgroup-util.c | 12 +++---- src/shared/fileio-label.c | 2 +- src/shared/fileio.c | 74 +++++++++++++++++++-------------------- src/shared/fileio.h | 10 ++++-- src/shared/smack-util.c | 2 +- src/shared/sysctl-util.c | 2 +- src/shared/util.c | 2 +- 9 files changed, 57 insertions(+), 53 deletions(-) diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c index 0cc2cdf99..dbe8cae60 100644 --- a/src/login/logind-dbus.c +++ b/src/login/logind-dbus.c @@ -1196,7 +1196,7 @@ static int trigger_device(Manager *m, struct udev_device *d) { if (!t) return -ENOMEM; - write_string_file(t, "change"); + write_string_file(t, "change", WRITE_STRING_FILE_CREATE); } return 0; @@ -1795,7 +1795,7 @@ static int nologin_timeout_handler( log_info("Creating /run/nologin, blocking further logins..."); - r = write_string_file_atomic("/run/nologin", "System is going down."); + r = write_string_file("/run/nologin", "System is going down.", WRITE_STRING_FILE_ATOMIC); if (r < 0) log_error_errno(r, "Failed to create /run/nologin: %m"); else diff --git a/src/shared/capability.c b/src/shared/capability.c index 58f00e6da..8dbe4da5b 100644 --- a/src/shared/capability.c +++ b/src/shared/capability.c @@ -204,7 +204,7 @@ static int drop_from_file(const char *fn, uint64_t drop) { if (asprintf(&p, "%u %u", lo, hi) < 0) return -ENOMEM; - r = write_string_file(fn, p); + r = write_string_file(fn, p, WRITE_STRING_FILE_CREATE); free(p); return r; diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c index b286243c3..cfee41ca3 100644 --- a/src/shared/cgroup-util.c +++ b/src/shared/cgroup-util.c @@ -645,7 +645,7 @@ int cg_attach(const char *controller, const char *path, pid_t pid) { snprintf(c, sizeof(c), PID_FMT"\n", pid); - return write_string_file_no_create(fs, c); + return write_string_file(fs, c, 0); } int cg_attach_fallback(const char *controller, const char *path, pid_t pid) { @@ -819,7 +819,7 @@ int cg_install_release_agent(const char *controller, const char *agent) { sc = strstrip(contents); if (sc[0] == 0) { - r = write_string_file_no_create(fs, agent); + r = write_string_file(fs, agent, 0); if (r < 0) return r; } else if (!streq(sc, agent)) @@ -839,7 +839,7 @@ int cg_install_release_agent(const char *controller, const char *agent) { sc = strstrip(contents); if (streq(sc, "0")) { - r = write_string_file_no_create(fs, "1"); + r = write_string_file(fs, "1", 0); if (r < 0) return r; @@ -860,7 +860,7 @@ int cg_uninstall_release_agent(const char *controller) { if (r < 0) return r; - r = write_string_file_no_create(fs, "0"); + r = write_string_file(fs, "0", 0); if (r < 0) return r; @@ -871,7 +871,7 @@ int cg_uninstall_release_agent(const char *controller) { if (r < 0) return r; - r = write_string_file_no_create(fs, ""); + r = write_string_file(fs, "", 0); if (r < 0) return r; @@ -1701,7 +1701,7 @@ int cg_set_attribute(const char *controller, const char *path, const char *attri if (r < 0) return r; - return write_string_file_no_create(p, value); + return write_string_file(p, value, 0); } int cg_get_attribute(const char *controller, const char *path, const char *attribute, char **ret) { diff --git a/src/shared/fileio-label.c b/src/shared/fileio-label.c index bec988ca7..f596f1d11 100644 --- a/src/shared/fileio-label.c +++ b/src/shared/fileio-label.c @@ -31,7 +31,7 @@ int write_string_file_atomic_label(const char *fn, const char *line) { if (r < 0) return r; - r = write_string_file_atomic(fn, line); + r = write_string_file(fn, line, WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC); mac_selinux_create_file_clear(); diff --git a/src/shared/fileio.c b/src/shared/fileio.c index 82b40aa7d..d592bf5ac 100644 --- a/src/shared/fileio.c +++ b/src/shared/fileio.c @@ -45,42 +45,7 @@ int write_string_stream(FILE *f, const char *line, bool enforce_newline) { return 0; } -int write_string_file(const char *fn, const char *line) { - _cleanup_fclose_ FILE *f = NULL; - - assert(fn); - assert(line); - - f = fopen(fn, "we"); - if (!f) - return -errno; - - return write_string_stream(f, line, true); -} - -int write_string_file_no_create(const char *fn, const char *line) { - _cleanup_fclose_ FILE *f = NULL; - int fd; - - assert(fn); - assert(line); - - /* We manually build our own version of fopen(..., "we") that - * works without O_CREAT */ - fd = open(fn, O_WRONLY|O_CLOEXEC|O_NOCTTY); - if (fd < 0) - return -errno; - - f = fdopen(fd, "we"); - if (!f) { - safe_close(fd); - return -errno; - } - - return write_string_stream(f, line, true); -} - -int write_string_file_atomic(const char *fn, const char *line) { +static int write_string_file_atomic(const char *fn, const char *line, bool enforce_newline) { _cleanup_fclose_ FILE *f = NULL; _cleanup_free_ char *p = NULL; int r; @@ -94,7 +59,7 @@ int write_string_file_atomic(const char *fn, const char *line) { fchmod_umask(fileno(f), 0644); - r = write_string_stream(f, line, true); + r = write_string_stream(f, line, enforce_newline); if (r >= 0) { if (rename(p, fn) < 0) r = -errno; @@ -106,6 +71,41 @@ int write_string_file_atomic(const char *fn, const char *line) { return r; } +int write_string_file(const char *fn, const char *line, WriteStringFileFlags flags) { + _cleanup_fclose_ FILE *f = NULL; + + assert(fn); + assert(line); + + if (flags & WRITE_STRING_FILE_ATOMIC) { + assert(flags & WRITE_STRING_FILE_CREATE); + + return write_string_file_atomic(fn, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE)); + } + + if (flags & WRITE_STRING_FILE_CREATE) { + f = fopen(fn, "we"); + if (!f) + return -errno; + } else { + int fd; + + /* We manually build our own version of fopen(..., "we") that + * works without O_CREAT */ + fd = open(fn, O_WRONLY|O_CLOEXEC|O_NOCTTY); + if (fd < 0) + return -errno; + + f = fdopen(fd, "we"); + if (!f) { + safe_close(fd); + return -errno; + } + } + + return write_string_stream(f, line, !(flags & WRITE_STRING_FILE_AVOID_NEWLINE)); +} + int read_one_line_file(const char *fn, char **line) { _cleanup_fclose_ FILE *f = NULL; char t[LINE_MAX], *c; diff --git a/src/shared/fileio.h b/src/shared/fileio.h index 989b904c2..2e8148ff2 100644 --- a/src/shared/fileio.h +++ b/src/shared/fileio.h @@ -25,10 +25,14 @@ #include "macro.h" +typedef enum { + WRITE_STRING_FILE_CREATE = 1, + WRITE_STRING_FILE_ATOMIC = 2, + WRITE_STRING_FILE_AVOID_NEWLINE = 4, +} WriteStringFileFlags; + int write_string_stream(FILE *f, const char *line, bool enforce_newline); -int write_string_file(const char *fn, const char *line); -int write_string_file_no_create(const char *fn, const char *line); -int write_string_file_atomic(const char *fn, const char *line); +int write_string_file(const char *fn, const char *line, WriteStringFileFlags flags); int read_one_line_file(const char *fn, char **line); int read_full_file(const char *fn, char **contents, size_t *size); diff --git a/src/shared/smack-util.c b/src/shared/smack-util.c index 2e24b1ea9..0c3697b61 100644 --- a/src/shared/smack-util.c +++ b/src/shared/smack-util.c @@ -139,7 +139,7 @@ int mac_smack_apply_pid(pid_t pid, const char *label) { return 0; p = procfs_file_alloca(pid, "attr/current"); - r = write_string_file(p, label); + r = write_string_file(p, label, WRITE_STRING_FILE_CREATE); if (r < 0) return r; #endif diff --git a/src/shared/sysctl-util.c b/src/shared/sysctl-util.c index 55f4e4860..232a00505 100644 --- a/src/shared/sysctl-util.c +++ b/src/shared/sysctl-util.c @@ -66,7 +66,7 @@ int sysctl_write(const char *property, const char *value) { log_debug("Setting '%s' to '%s'", property, value); p = strjoina("/proc/sys/", property); - return write_string_file(p, value); + return write_string_file(p, value, WRITE_STRING_FILE_CREATE); } int sysctl_read(const char *property, char **content) { diff --git a/src/shared/util.c b/src/shared/util.c index 727be56f5..950519ed0 100644 --- a/src/shared/util.c +++ b/src/shared/util.c @@ -4716,7 +4716,7 @@ int update_reboot_param_file(const char *param) { if (param) { - r = write_string_file(REBOOT_PARAM_FILE, param); + r = write_string_file(REBOOT_PARAM_FILE, param, WRITE_STRING_FILE_CREATE); if (r < 0) log_error("Failed to write reboot param to " REBOOT_PARAM_FILE": %s", strerror(-r)); -- 2.30.2