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-rw-r--r--src/basic/fileio.c817
1 files changed, 817 insertions, 0 deletions
diff --git a/src/basic/fileio.c b/src/basic/fileio.c
new file mode 100644
index 0000000000..ff6b1a7ed7
--- /dev/null
+++ b/src/basic/fileio.c
@@ -0,0 +1,817 @@
+/*-*- 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 Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <unistd.h>
+
+#include "util.h"
+#include "strv.h"
+#include "utf8.h"
+#include "ctype.h"
+#include "fileio.h"
+
+int write_string_stream(FILE *f, const char *line) {
+ assert(f);
+ assert(line);
+
+ errno = 0;
+
+ fputs(line, f);
+ if (!endswith(line, "\n"))
+ fputc('\n', f);
+
+ fflush(f);
+
+ if (ferror(f))
+ return errno ? -errno : -EIO;
+
+ 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);
+}
+
+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);
+}
+
+int write_string_file_atomic(const char *fn, const char *line) {
+ _cleanup_fclose_ FILE *f = NULL;
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ assert(fn);
+ assert(line);
+
+ r = fopen_temporary(fn, &f, &p);
+ if (r < 0)
+ return r;
+
+ fchmod_umask(fileno(f), 0644);
+
+ r = write_string_stream(f, line);
+ if (r >= 0) {
+ if (rename(p, fn) < 0)
+ r = -errno;
+ }
+
+ if (r < 0)
+ unlink(p);
+
+ return r;
+}
+
+int read_one_line_file(const char *fn, char **line) {
+ _cleanup_fclose_ FILE *f = NULL;
+ char t[LINE_MAX], *c;
+
+ assert(fn);
+ assert(line);
+
+ f = fopen(fn, "re");
+ if (!f)
+ return -errno;
+
+ if (!fgets(t, sizeof(t), f)) {
+
+ if (ferror(f))
+ return errno ? -errno : -EIO;
+
+ t[0] = 0;
+ }
+
+ c = strdup(t);
+ if (!c)
+ return -ENOMEM;
+ truncate_nl(c);
+
+ *line = c;
+ return 0;
+}
+
+int read_full_stream(FILE *f, char **contents, size_t *size) {
+ size_t n, l;
+ _cleanup_free_ char *buf = NULL;
+ struct stat st;
+
+ assert(f);
+ assert(contents);
+
+ if (fstat(fileno(f), &st) < 0)
+ return -errno;
+
+ n = LINE_MAX;
+
+ if (S_ISREG(st.st_mode)) {
+
+ /* Safety check */
+ if (st.st_size > 4*1024*1024)
+ return -E2BIG;
+
+ /* Start with the right file size, but be prepared for
+ * files from /proc which generally report a file size
+ * of 0 */
+ if (st.st_size > 0)
+ n = st.st_size;
+ }
+
+ l = 0;
+ for (;;) {
+ char *t;
+ size_t k;
+
+ t = realloc(buf, n+1);
+ if (!t)
+ return -ENOMEM;
+
+ buf = t;
+ k = fread(buf + l, 1, n - l, f);
+
+ if (k <= 0) {
+ if (ferror(f))
+ return -errno;
+
+ break;
+ }
+
+ l += k;
+ n *= 2;
+
+ /* Safety check */
+ if (n > 4*1024*1024)
+ return -E2BIG;
+ }
+
+ buf[l] = 0;
+ *contents = buf;
+ buf = NULL; /* do not free */
+
+ if (size)
+ *size = l;
+
+ return 0;
+}
+
+int read_full_file(const char *fn, char **contents, size_t *size) {
+ _cleanup_fclose_ FILE *f = NULL;
+
+ assert(fn);
+ assert(contents);
+
+ f = fopen(fn, "re");
+ if (!f)
+ return -errno;
+
+ return read_full_stream(f, contents, size);
+}
+
+static int parse_env_file_internal(
+ FILE *f,
+ const char *fname,
+ const char *newline,
+ int (*push) (const char *filename, unsigned line,
+ const char *key, char *value, void *userdata, int *n_pushed),
+ void *userdata,
+ int *n_pushed) {
+
+ _cleanup_free_ char *contents = NULL, *key = NULL;
+ size_t key_alloc = 0, n_key = 0, value_alloc = 0, n_value = 0, last_value_whitespace = (size_t) -1, last_key_whitespace = (size_t) -1;
+ char *p, *value = NULL;
+ int r;
+ unsigned line = 1;
+
+ enum {
+ PRE_KEY,
+ KEY,
+ PRE_VALUE,
+ VALUE,
+ VALUE_ESCAPE,
+ SINGLE_QUOTE_VALUE,
+ SINGLE_QUOTE_VALUE_ESCAPE,
+ DOUBLE_QUOTE_VALUE,
+ DOUBLE_QUOTE_VALUE_ESCAPE,
+ COMMENT,
+ COMMENT_ESCAPE
+ } state = PRE_KEY;
+
+ assert(newline);
+
+ if (f)
+ r = read_full_stream(f, &contents, NULL);
+ else
+ r = read_full_file(fname, &contents, NULL);
+ if (r < 0)
+ return r;
+
+ for (p = contents; *p; p++) {
+ char c = *p;
+
+ switch (state) {
+
+ case PRE_KEY:
+ if (strchr(COMMENTS, c))
+ state = COMMENT;
+ else if (!strchr(WHITESPACE, c)) {
+ state = KEY;
+ last_key_whitespace = (size_t) -1;
+
+ if (!GREEDY_REALLOC(key, key_alloc, n_key+2)) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ key[n_key++] = c;
+ }
+ break;
+
+ case KEY:
+ if (strchr(newline, c)) {
+ state = PRE_KEY;
+ line ++;
+ n_key = 0;
+ } else if (c == '=') {
+ state = PRE_VALUE;
+ last_value_whitespace = (size_t) -1;
+ } else {
+ if (!strchr(WHITESPACE, c))
+ last_key_whitespace = (size_t) -1;
+ else if (last_key_whitespace == (size_t) -1)
+ last_key_whitespace = n_key;
+
+ if (!GREEDY_REALLOC(key, key_alloc, n_key+2)) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ key[n_key++] = c;
+ }
+
+ break;
+
+ case PRE_VALUE:
+ if (strchr(newline, c)) {
+ state = PRE_KEY;
+ line ++;
+ key[n_key] = 0;
+
+ if (value)
+ value[n_value] = 0;
+
+ /* strip trailing whitespace from key */
+ if (last_key_whitespace != (size_t) -1)
+ key[last_key_whitespace] = 0;
+
+ r = push(fname, line, key, value, userdata, n_pushed);
+ if (r < 0)
+ goto fail;
+
+ n_key = 0;
+ value = NULL;
+ value_alloc = n_value = 0;
+
+ } else if (c == '\'')
+ state = SINGLE_QUOTE_VALUE;
+ else if (c == '\"')
+ state = DOUBLE_QUOTE_VALUE;
+ else if (c == '\\')
+ state = VALUE_ESCAPE;
+ else if (!strchr(WHITESPACE, c)) {
+ state = VALUE;
+
+ if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ value[n_value++] = c;
+ }
+
+ break;
+
+ case VALUE:
+ if (strchr(newline, c)) {
+ state = PRE_KEY;
+ line ++;
+
+ key[n_key] = 0;
+
+ if (value)
+ value[n_value] = 0;
+
+ /* Chomp off trailing whitespace from value */
+ if (last_value_whitespace != (size_t) -1)
+ value[last_value_whitespace] = 0;
+
+ /* strip trailing whitespace from key */
+ if (last_key_whitespace != (size_t) -1)
+ key[last_key_whitespace] = 0;
+
+ r = push(fname, line, key, value, userdata, n_pushed);
+ if (r < 0)
+ goto fail;
+
+ n_key = 0;
+ value = NULL;
+ value_alloc = n_value = 0;
+
+ } else if (c == '\\') {
+ state = VALUE_ESCAPE;
+ last_value_whitespace = (size_t) -1;
+ } else {
+ if (!strchr(WHITESPACE, c))
+ last_value_whitespace = (size_t) -1;
+ else if (last_value_whitespace == (size_t) -1)
+ last_value_whitespace = n_value;
+
+ if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ value[n_value++] = c;
+ }
+
+ break;
+
+ case VALUE_ESCAPE:
+ state = VALUE;
+
+ if (!strchr(newline, c)) {
+ /* Escaped newlines we eat up entirely */
+ if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ value[n_value++] = c;
+ }
+ break;
+
+ case SINGLE_QUOTE_VALUE:
+ if (c == '\'')
+ state = PRE_VALUE;
+ else if (c == '\\')
+ state = SINGLE_QUOTE_VALUE_ESCAPE;
+ else {
+ if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ value[n_value++] = c;
+ }
+
+ break;
+
+ case SINGLE_QUOTE_VALUE_ESCAPE:
+ state = SINGLE_QUOTE_VALUE;
+
+ if (!strchr(newline, c)) {
+ if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ value[n_value++] = c;
+ }
+ break;
+
+ case DOUBLE_QUOTE_VALUE:
+ if (c == '\"')
+ state = PRE_VALUE;
+ else if (c == '\\')
+ state = DOUBLE_QUOTE_VALUE_ESCAPE;
+ else {
+ if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ value[n_value++] = c;
+ }
+
+ break;
+
+ case DOUBLE_QUOTE_VALUE_ESCAPE:
+ state = DOUBLE_QUOTE_VALUE;
+
+ if (!strchr(newline, c)) {
+ if (!GREEDY_REALLOC(value, value_alloc, n_value+2)) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ value[n_value++] = c;
+ }
+ break;
+
+ case COMMENT:
+ if (c == '\\')
+ state = COMMENT_ESCAPE;
+ else if (strchr(newline, c)) {
+ state = PRE_KEY;
+ line ++;
+ }
+ break;
+
+ case COMMENT_ESCAPE:
+ state = COMMENT;
+ break;
+ }
+ }
+
+ if (state == PRE_VALUE ||
+ state == VALUE ||
+ state == VALUE_ESCAPE ||
+ state == SINGLE_QUOTE_VALUE ||
+ state == SINGLE_QUOTE_VALUE_ESCAPE ||
+ state == DOUBLE_QUOTE_VALUE ||
+ state == DOUBLE_QUOTE_VALUE_ESCAPE) {
+
+ key[n_key] = 0;
+
+ if (value)
+ value[n_value] = 0;
+
+ if (state == VALUE)
+ if (last_value_whitespace != (size_t) -1)
+ value[last_value_whitespace] = 0;
+
+ /* strip trailing whitespace from key */
+ if (last_key_whitespace != (size_t) -1)
+ key[last_key_whitespace] = 0;
+
+ r = push(fname, line, key, value, userdata, n_pushed);
+ if (r < 0)
+ goto fail;
+ }
+
+ return 0;
+
+fail:
+ free(value);
+ return r;
+}
+
+static int parse_env_file_push(
+ const char *filename, unsigned line,
+ const char *key, char *value,
+ void *userdata,
+ int *n_pushed) {
+
+ const char *k;
+ va_list aq, *ap = userdata;
+
+ if (!utf8_is_valid(key)) {
+ _cleanup_free_ char *p;
+
+ p = utf8_escape_invalid(key);
+ log_error("%s:%u: invalid UTF-8 in key '%s', ignoring.", strna(filename), line, p);
+ return -EINVAL;
+ }
+
+ if (value && !utf8_is_valid(value)) {
+ _cleanup_free_ char *p;
+
+ p = utf8_escape_invalid(value);
+ log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, p);
+ return -EINVAL;
+ }
+
+ va_copy(aq, *ap);
+
+ while ((k = va_arg(aq, const char *))) {
+ char **v;
+
+ v = va_arg(aq, char **);
+
+ if (streq(key, k)) {
+ va_end(aq);
+ free(*v);
+ *v = value;
+
+ if (n_pushed)
+ (*n_pushed)++;
+
+ return 1;
+ }
+ }
+
+ va_end(aq);
+ free(value);
+
+ return 0;
+}
+
+int parse_env_file(
+ const char *fname,
+ const char *newline, ...) {
+
+ va_list ap;
+ int r, n_pushed = 0;
+
+ if (!newline)
+ newline = NEWLINE;
+
+ va_start(ap, newline);
+ r = parse_env_file_internal(NULL, fname, newline, parse_env_file_push, &ap, &n_pushed);
+ va_end(ap);
+
+ return r < 0 ? r : n_pushed;
+}
+
+static int load_env_file_push(
+ const char *filename, unsigned line,
+ const char *key, char *value,
+ void *userdata,
+ int *n_pushed) {
+ char ***m = userdata;
+ char *p;
+ int r;
+
+ if (!utf8_is_valid(key)) {
+ _cleanup_free_ char *t = utf8_escape_invalid(key);
+
+ log_error("%s:%u: invalid UTF-8 for key '%s', ignoring.", strna(filename), line, t);
+ return -EINVAL;
+ }
+
+ if (value && !utf8_is_valid(value)) {
+ _cleanup_free_ char *t = utf8_escape_invalid(value);
+
+ log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, t);
+ return -EINVAL;
+ }
+
+ p = strjoin(key, "=", strempty(value), NULL);
+ if (!p)
+ return -ENOMEM;
+
+ r = strv_consume(m, p);
+ if (r < 0)
+ return r;
+
+ if (n_pushed)
+ (*n_pushed)++;
+
+ free(value);
+ return 0;
+}
+
+int load_env_file(FILE *f, const char *fname, const char *newline, char ***rl) {
+ char **m = NULL;
+ int r;
+
+ if (!newline)
+ newline = NEWLINE;
+
+ r = parse_env_file_internal(f, fname, newline, load_env_file_push, &m, NULL);
+ if (r < 0) {
+ strv_free(m);
+ return r;
+ }
+
+ *rl = m;
+ return 0;
+}
+
+static int load_env_file_push_pairs(
+ const char *filename, unsigned line,
+ const char *key, char *value,
+ void *userdata,
+ int *n_pushed) {
+ char ***m = userdata;
+ int r;
+
+ if (!utf8_is_valid(key)) {
+ _cleanup_free_ char *t = utf8_escape_invalid(key);
+
+ log_error("%s:%u: invalid UTF-8 for key '%s', ignoring.", strna(filename), line, t);
+ return -EINVAL;
+ }
+
+ if (value && !utf8_is_valid(value)) {
+ _cleanup_free_ char *t = utf8_escape_invalid(value);
+
+ log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, t);
+ return -EINVAL;
+ }
+
+ r = strv_extend(m, key);
+ if (r < 0)
+ return -ENOMEM;
+
+ if (!value) {
+ r = strv_extend(m, "");
+ if (r < 0)
+ return -ENOMEM;
+ } else {
+ r = strv_push(m, value);
+ if (r < 0)
+ return r;
+ }
+
+ if (n_pushed)
+ (*n_pushed)++;
+
+ return 0;
+}
+
+int load_env_file_pairs(FILE *f, const char *fname, const char *newline, char ***rl) {
+ char **m = NULL;
+ int r;
+
+ if (!newline)
+ newline = NEWLINE;
+
+ r = parse_env_file_internal(f, fname, newline, load_env_file_push_pairs, &m, NULL);
+ if (r < 0) {
+ strv_free(m);
+ return r;
+ }
+
+ *rl = m;
+ return 0;
+}
+
+static void write_env_var(FILE *f, const char *v) {
+ const char *p;
+
+ p = strchr(v, '=');
+ if (!p) {
+ /* Fallback */
+ fputs(v, f);
+ fputc('\n', f);
+ return;
+ }
+
+ p++;
+ fwrite(v, 1, p-v, f);
+
+ if (string_has_cc(p, NULL) || chars_intersect(p, WHITESPACE SHELL_NEED_QUOTES)) {
+ fputc('\"', f);
+
+ for (; *p; p++) {
+ if (strchr(SHELL_NEED_ESCAPE, *p))
+ fputc('\\', f);
+
+ fputc(*p, f);
+ }
+
+ fputc('\"', f);
+ } else
+ fputs(p, f);
+
+ fputc('\n', f);
+}
+
+int write_env_file(const char *fname, char **l) {
+ _cleanup_fclose_ FILE *f = NULL;
+ _cleanup_free_ char *p = NULL;
+ char **i;
+ int r;
+
+ assert(fname);
+
+ r = fopen_temporary(fname, &f, &p);
+ if (r < 0)
+ return r;
+
+ fchmod_umask(fileno(f), 0644);
+
+ STRV_FOREACH(i, l)
+ write_env_var(f, *i);
+
+ r = fflush_and_check(f);
+ if (r >= 0) {
+ if (rename(p, fname) >= 0)
+ return 0;
+
+ r = -errno;
+ }
+
+ unlink(p);
+ return r;
+}
+
+int executable_is_script(const char *path, char **interpreter) {
+ int r;
+ _cleanup_free_ char *line = NULL;
+ int len;
+ char *ans;
+
+ assert(path);
+
+ r = read_one_line_file(path, &line);
+ if (r < 0)
+ return r;
+
+ if (!startswith(line, "#!"))
+ return 0;
+
+ ans = strstrip(line + 2);
+ len = strcspn(ans, " \t");
+
+ if (len == 0)
+ return 0;
+
+ ans = strndup(ans, len);
+ if (!ans)
+ return -ENOMEM;
+
+ *interpreter = ans;
+ return 1;
+}
+
+/**
+ * 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.
+ */
+int get_status_field(const char *filename, const char *pattern, char **field) {
+ _cleanup_free_ char *status = NULL;
+ char *t;
+ size_t len;
+ int r;
+
+ assert(filename);
+ assert(pattern);
+ assert(field);
+
+ r = read_full_file(filename, &status, NULL);
+ if (r < 0)
+ return r;
+
+ t = strstr(status, pattern);
+ if (!t)
+ return -ENOENT;
+
+ t += strlen(pattern);
+ if (*t) {
+ t += strspn(t, " \t");
+
+ /* Also skip zeros, because when this is used for
+ * capabilities, we don't want the zeros. This way the
+ * same capability set always maps to the same string,
+ * irrespective of the total capability set size. For
+ * other numbers it shouldn't matter. */
+ t += strspn(t, "0");
+ /* Back off one char if there's nothing but whitespace
+ and zeros */
+ if (!*t || isspace(*t))
+ t --;
+ }
+
+ len = strcspn(t, WHITESPACE);
+
+ *field = strndup(t, len);
+ if (!*field)
+ return -ENOMEM;
+
+ return 0;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-04 07:40:42 +0000