diff options
Diffstat (limited to 'src/basic/fileio.c')
| -rw-r--r-- | src/basic/fileio.c | 354 |
1 files changed, 341 insertions, 13 deletions
diff --git a/src/basic/fileio.c b/src/basic/fileio.c index 4a9105f421..619dafb517 100644 --- a/src/basic/fileio.c +++ b/src/basic/fileio.c @@ -21,11 +21,20 @@ #include <unistd.h> -#include "util.h" -#include "strv.h" -#include "utf8.h" +#include "alloc-util.h" #include "ctype.h" +#include "escape.h" +#include "fd-util.h" #include "fileio.h" +#include "fs-util.h" +#include "hexdecoct.h" +#include "path-util.h" +#include "random-util.h" +#include "string-util.h" +#include "strv.h" +#include "umask-util.h" +#include "utf8.h" +#include "util.h" int write_string_stream(FILE *f, const char *line, bool enforce_newline) { @@ -51,7 +60,7 @@ static int write_string_file_atomic(const char *fn, const char *line, bool enfor if (r < 0) return r; - fchmod_umask(fileno(f), 0644); + (void) fchmod_umask(fileno(f), 0644); r = write_string_stream(f, line, enforce_newline); if (r >= 0) { @@ -60,7 +69,7 @@ static int write_string_file_atomic(const char *fn, const char *line, bool enfor } if (r < 0) - unlink(p); + (void) unlink(p); return r; } @@ -775,15 +784,19 @@ int executable_is_script(const char *path, char **interpreter) { /** * Retrieve one field from a file like /proc/self/status. pattern - * should start with '\n' and end with a ':'. Whitespace and zeros - * after the ':' will be skipped. field must be freed afterwards. + * should not include whitespace or the delimiter (':'). pattern matches only + * the beginning of a line. Whitespace before ':' is skipped. Whitespace and + * zeros after the ':' will be skipped. field must be freed afterwards. + * terminator specifies the terminating characters of the field value (not + * included in the value). */ -int get_status_field(const char *filename, const char *pattern, char **field) { +int get_proc_field(const char *filename, const char *pattern, const char *terminator, char **field) { _cleanup_free_ char *status = NULL; char *t, *f; size_t len; int r; + assert(terminator); assert(filename); assert(pattern); assert(field); @@ -792,11 +805,31 @@ int get_status_field(const char *filename, const char *pattern, char **field) { if (r < 0) return r; - t = strstr(status, pattern); - if (!t) - return -ENOENT; + t = status; + + do { + bool pattern_ok; + + do { + t = strstr(t, pattern); + if (!t) + return -ENOENT; + + /* Check that pattern occurs in beginning of line. */ + pattern_ok = (t == status || t[-1] == '\n'); + + t += strlen(pattern); + + } while (!pattern_ok); + + t += strspn(t, " \t"); + if (!*t) + return -ENOENT; + + } while (*t != ':'); + + t++; - t += strlen(pattern); if (*t) { t += strspn(t, " \t"); @@ -812,7 +845,7 @@ int get_status_field(const char *filename, const char *pattern, char **field) { t --; } - len = strcspn(t, WHITESPACE); + len = strcspn(t, terminator); f = strndup(t, len); if (!f) @@ -821,3 +854,298 @@ int get_status_field(const char *filename, const char *pattern, char **field) { *field = f; return 0; } + +DIR *xopendirat(int fd, const char *name, int flags) { + int nfd; + DIR *d; + + assert(!(flags & O_CREAT)); + + nfd = openat(fd, name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|flags, 0); + if (nfd < 0) + return NULL; + + d = fdopendir(nfd); + if (!d) { + safe_close(nfd); + return NULL; + } + + return d; +} + +static int search_and_fopen_internal(const char *path, const char *mode, const char *root, char **search, FILE **_f) { + char **i; + + assert(path); + assert(mode); + assert(_f); + + if (!path_strv_resolve_uniq(search, root)) + return -ENOMEM; + + STRV_FOREACH(i, search) { + _cleanup_free_ char *p = NULL; + FILE *f; + + if (root) + p = strjoin(root, *i, "/", path, NULL); + else + p = strjoin(*i, "/", path, NULL); + if (!p) + return -ENOMEM; + + f = fopen(p, mode); + if (f) { + *_f = f; + return 0; + } + + if (errno != ENOENT) + return -errno; + } + + return -ENOENT; +} + +int search_and_fopen(const char *path, const char *mode, const char *root, const char **search, FILE **_f) { + _cleanup_strv_free_ char **copy = NULL; + + assert(path); + assert(mode); + assert(_f); + + if (path_is_absolute(path)) { + FILE *f; + + f = fopen(path, mode); + if (f) { + *_f = f; + return 0; + } + + return -errno; + } + + copy = strv_copy((char**) search); + if (!copy) + return -ENOMEM; + + return search_and_fopen_internal(path, mode, root, copy, _f); +} + +int search_and_fopen_nulstr(const char *path, const char *mode, const char *root, const char *search, FILE **_f) { + _cleanup_strv_free_ char **s = NULL; + + if (path_is_absolute(path)) { + FILE *f; + + f = fopen(path, mode); + if (f) { + *_f = f; + return 0; + } + + return -errno; + } + + s = strv_split_nulstr(search); + if (!s) + return -ENOMEM; + + return search_and_fopen_internal(path, mode, root, s, _f); +} + +int fopen_temporary(const char *path, FILE **_f, char **_temp_path) { + FILE *f; + char *t; + int r, fd; + + assert(path); + assert(_f); + assert(_temp_path); + + r = tempfn_xxxxxx(path, NULL, &t); + if (r < 0) + return r; + + fd = mkostemp_safe(t, O_WRONLY|O_CLOEXEC); + if (fd < 0) { + free(t); + return -errno; + } + + f = fdopen(fd, "we"); + if (!f) { + unlink_noerrno(t); + free(t); + safe_close(fd); + return -errno; + } + + *_f = f; + *_temp_path = t; + + return 0; +} + +int fflush_and_check(FILE *f) { + assert(f); + + errno = 0; + fflush(f); + + if (ferror(f)) + return errno ? -errno : -EIO; + + return 0; +} + +/* This is much like like mkostemp() but is subject to umask(). */ +int mkostemp_safe(char *pattern, int flags) { + _cleanup_umask_ mode_t u; + int fd; + + assert(pattern); + + u = umask(077); + + fd = mkostemp(pattern, flags); + if (fd < 0) + return -errno; + + return fd; +} + +int open_tmpfile(const char *path, int flags) { + char *p; + int fd; + + assert(path); + +#ifdef O_TMPFILE + /* Try O_TMPFILE first, if it is supported */ + fd = open(path, flags|O_TMPFILE|O_EXCL, S_IRUSR|S_IWUSR); + if (fd >= 0) + return fd; +#endif + + /* Fall back to unguessable name + unlinking */ + p = strjoina(path, "/systemd-tmp-XXXXXX"); + + fd = mkostemp_safe(p, flags); + if (fd < 0) + return fd; + + unlink(p); + return fd; +} + +int tempfn_xxxxxx(const char *p, const char *extra, char **ret) { + const char *fn; + char *t; + + assert(p); + assert(ret); + + /* + * Turns this: + * /foo/bar/waldo + * + * Into this: + * /foo/bar/.#<extra>waldoXXXXXX + */ + + fn = basename(p); + if (!filename_is_valid(fn)) + return -EINVAL; + + if (extra == NULL) + extra = ""; + + t = new(char, strlen(p) + 2 + strlen(extra) + 6 + 1); + if (!t) + return -ENOMEM; + + strcpy(stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn), "XXXXXX"); + + *ret = path_kill_slashes(t); + return 0; +} + +int tempfn_random(const char *p, const char *extra, char **ret) { + const char *fn; + char *t, *x; + uint64_t u; + unsigned i; + + assert(p); + assert(ret); + + /* + * Turns this: + * /foo/bar/waldo + * + * Into this: + * /foo/bar/.#<extra>waldobaa2a261115984a9 + */ + + fn = basename(p); + if (!filename_is_valid(fn)) + return -EINVAL; + + if (!extra) + extra = ""; + + t = new(char, strlen(p) + 2 + strlen(extra) + 16 + 1); + if (!t) + return -ENOMEM; + + x = stpcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), extra), fn); + + u = random_u64(); + for (i = 0; i < 16; i++) { + *(x++) = hexchar(u & 0xF); + u >>= 4; + } + + *x = 0; + + *ret = path_kill_slashes(t); + return 0; +} + +int tempfn_random_child(const char *p, const char *extra, char **ret) { + char *t, *x; + uint64_t u; + unsigned i; + + assert(p); + assert(ret); + + /* Turns this: + * /foo/bar/waldo + * Into this: + * /foo/bar/waldo/.#<extra>3c2b6219aa75d7d0 + */ + + if (!extra) + extra = ""; + + t = new(char, strlen(p) + 3 + strlen(extra) + 16 + 1); + if (!t) + return -ENOMEM; + + x = stpcpy(stpcpy(stpcpy(t, p), "/.#"), extra); + + u = random_u64(); + for (i = 0; i < 16; i++) { + *(x++) = hexchar(u & 0xF); + u >>= 4; + } + + *x = 0; + + *ret = path_kill_slashes(t); + return 0; +} |