diff options
Diffstat (limited to 'src/shared/fileio.c')
-rw-r--r-- | src/shared/fileio.c | 596 |
1 files changed, 596 insertions, 0 deletions
diff --git a/src/shared/fileio.c b/src/shared/fileio.c new file mode 100644 index 0000000000..ad068bf30d --- /dev/null +++ b/src/shared/fileio.c @@ -0,0 +1,596 @@ +/*-*- 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_to_file(FILE *f, const char *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_to_file(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); + + 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_value_whitespace = (size_t) -1, last_key_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; + last_key_whitespace = (size_t) -1; + + 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; + 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((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 */ + if (last_key_whitespace != (size_t) -1) + key[last_key_whitespace] = 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 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(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_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((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; + + 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(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; +} |