fileio.c revision 98f59e59e0c31ffcb953d3a7dba0da5e6f2f55f7
/*-*- 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 "fileio.h"
#include "util.h"
#include "strv.h"
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;
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_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);
errno = 0;
fputs(line, f);
if (!endswith(line, "\n"))
fputc('\n', f);
fflush(f);
if (ferror(f))
r = errno ? -errno : -EIO;
else {
if (rename(p, fn) < 0)
r = -errno;
else
r = 0;
}
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_file(const char *fn, char **contents, size_t *size) {
_cleanup_fclose_ FILE *f = NULL;
size_t n, l;
_cleanup_free_ char *buf = NULL;
struct stat st;
assert(fn);
assert(contents);
f = fopen(fn, "re");
if (!f)
return -errno;
if (fstat(fileno(f), &st) < 0)
return -errno;
/* Safety check */
if (st.st_size > 4*1024*1024)
return -E2BIG;
n = st.st_size > 0 ? st.st_size : LINE_MAX;
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;
if (size)
*size = l;
return 0;
}
static int parse_env_file_internal(
const char *fname,
const char *newline,
int (*push) (const char *key, char *value, void *userdata),
void *userdata) {
_cleanup_free_ char *contents = NULL, *key = NULL;
size_t key_alloc = 0, n_key = 0, value_alloc = 0, n_value = 0, last_whitespace = (size_t) -1;
char *p, *value = NULL;
int r;
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(fname);
assert(newline);
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;
if (!greedy_realloc((void**) &key, &key_alloc, n_key+2)) {
r = -ENOMEM;
goto fail;
}
key[n_key++] = c;
}
break;
case KEY:
if (strchr(newline, c)) {
state = PRE_KEY;
n_key = 0;
} else if (c == '=')
state = PRE_VALUE;
else {
if (!greedy_realloc((void**) &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;
key[n_key] = 0;
if (value)
value[n_value] = 0;
/* strip trailing whitespace from key */
while(n_key && strchr(WHITESPACE, key[--n_key]))
key[n_key]=0;
r = push(key, value, userdata);
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((void**) &value, &value_alloc, n_value+2)) {
r = -ENOMEM;
goto fail;
}
value[n_value++] = c;
}
break;
case VALUE:
if (strchr(newline, c)) {
state = PRE_KEY;
key[n_key] = 0;
if (value)
value[n_value] = 0;
/* Chomp off trailing whitespace */
if (last_whitespace != (size_t) -1)
value[last_whitespace] = 0;
/* strip trailing whitespace from key */
while(n_key && strchr(WHITESPACE, key[--n_key]))
key[n_key]=0;
r = push(key, value, userdata);
if (r < 0)
goto fail;
n_key = 0;
value = NULL;
value_alloc = n_value = 0;
} else if (c == '\\') {
state = VALUE_ESCAPE;
last_whitespace = (size_t) -1;
} else {
if (!strchr(WHITESPACE, c))
last_whitespace = (size_t) -1;
else if (last_whitespace == (size_t) -1)
last_whitespace = n_value;
if (!greedy_realloc((void**) &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((void**) &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((void**) &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((void**) &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((void**) &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((void**) &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;
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;
/* strip trailing whitespace from key */
while(n_key && strchr(WHITESPACE, key[--n_key]))
key[n_key]=0;
r = push(key, value, userdata);
if (r < 0)
goto fail;
}
return 0;
fail:
free(value);
return r;
}
static int parse_env_file_push(const char *key, char *value, void *userdata) {
const char *k;
va_list* ap = (va_list*) userdata;
va_list aq;
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;
return 1;
}
}
va_end(aq);
free(value);
return 0;
}
int parse_env_file(
const char *fname,
const char *newline, ...) {
va_list ap;
int r;
if (!newline)
newline = NEWLINE;
va_start(ap, newline);
r = parse_env_file_internal(fname, newline, parse_env_file_push, &ap);
va_end(ap);
return r;
}
static int load_env_file_push(const char *key, char *value, void *userdata) {
char ***m = userdata;
char *p;
int r;
p = strjoin(key, "=", strempty(value), NULL);
if (!p)
return -ENOMEM;
r = strv_push(m, p);
if (r < 0) {
free(p);
return r;
}
free(value);
return 0;
}
int load_env_file(const char *fname, const char *newline, char ***rl) {
char **m = NULL;
int r;
if (!newline)
newline = NEWLINE;
r = parse_env_file_internal(fname, newline, load_env_file_push, &m);
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) || chars_intersect(p, WHITESPACE "\'\"\\`$")) {
fputc('\"', f);
for (; *p; p++) {
if (strchr("\'\"\\`$", *p))
fputc('\\', f);
fputc(*p, f);
}
fputc('\"', f);
} else
fputs(p, f);
fputc('\n', f);
}
int write_env_file(const char *fname, char **l) {
char **i;
_cleanup_free_ char *p = NULL;
_cleanup_fclose_ FILE *f = NULL;
int r;
r = fopen_temporary(fname, &f, &p);
if (r < 0)
return r;
fchmod_umask(fileno(f), 0644);
errno = 0;
STRV_FOREACH(i, l)
write_env_var(f, *i);
fflush(f);
if (ferror(f))
r = errno ? -errno : -EIO;
else {
if (rename(p, fname) < 0)
r = -errno;
else
r = 0;
}
if (r < 0)
unlink(p);
return r;
}