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authorDavid Oberhollenzer <david.oberhollenzer@tele2.at>2018-04-12 06:15:02 +0200
committerDavid Oberhollenzer <david.oberhollenzer@tele2.at>2018-04-12 12:05:15 +0200
commit55d4a328c9fa369611115a066f4f305f2b74dafd (patch)
tree96933fd0b123850219c8d779077874d6180e5d4c /initd/env.c
parent82cd18107f5283054aa8bad27b7741eaf0cfea4c (diff)
Read environment for init from config file
Signed-off-by: David Oberhollenzer <david.oberhollenzer@tele2.at>
Diffstat (limited to 'initd/env.c')
-rw-r--r--initd/env.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/initd/env.c b/initd/env.c
new file mode 100644
index 0000000..c6a9e65
--- /dev/null
+++ b/initd/env.c
@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * Copyright (C) 2018 - David Oberhollenzer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <fcntl.h>
+
+#include "init.h"
+#include "util.h"
+
+struct entry {
+ struct entry *next;
+ char data[];
+};
+
+extern char **environ;
+
+static void free_list(struct entry *list)
+{
+ struct entry *e;
+
+ while (list != NULL) {
+ e = list;
+ list = list->next;
+ free(e);
+ }
+}
+
+static struct entry *parse_list(rdline_t *rd)
+{
+ struct entry *e, *list = NULL;
+ char *ptr;
+
+ while (rdline(rd) == 0) {
+ ptr = rd->buffer;
+
+ while (*ptr != '\0' && *ptr != ' ' && *ptr != '=')
+ ++ptr;
+
+ if (*ptr == ' ')
+ memmove(ptr, ptr + 1, strlen(ptr + 1) + 1);
+
+ if (*(ptr++) != '=') {
+ fprintf(stderr, "%s: %zu: line is not of the shape "
+ "'key = value', skipping\n",
+ rd->filename, rd->lineno);
+ continue;
+ }
+
+ if (*ptr == ' ')
+ memmove(ptr, ptr + 1, strlen(ptr + 1) + 1);
+
+ if (unescape(ptr)) {
+ fprintf(stderr, "%s: %zu: malformed string constant, "
+ "skipping\n",
+ rd->filename, rd->lineno);
+ continue;
+ }
+
+ e = calloc(1, sizeof(*e) + strlen(rd->buffer) + 1);
+ if (e == NULL)
+ goto fail_oom;
+
+ strcpy(e->data, rd->buffer);
+ e->next = list;
+ list = e;
+ }
+
+ return list;
+fail_oom:
+ fputs("out of memory\n", stderr);
+ free_list(list);
+ return NULL;
+}
+
+static struct entry *list_from_file(void)
+{
+ struct entry *list;
+ rdline_t rd;
+ int fd;
+
+ fd = open(ENVFILE, O_RDONLY);
+ if (fd < 0) {
+ perror(ENVFILE);
+ return NULL;
+ }
+
+ rdline_init(&rd, fd, ENVFILE, 0, NULL);
+ list = parse_list(&rd);
+ close(fd);
+ return list;
+}
+
+int initenv(void)
+{
+ struct entry *list, *e;
+ int i, count;
+ char **envp;
+
+ list = list_from_file();
+ if (list == NULL)
+ return -1;
+
+ for (count = 0, e = list; e != NULL; e = e->next)
+ ++count;
+
+ envp = malloc((count + 1) * sizeof(char *));
+ if (envp == NULL) {
+ fputs("out of memory\n", stderr);
+ free_list(list);
+ return -1;
+ }
+
+ for (i = 0, e = list; e != NULL; e = e->next)
+ envp[i] = e->data;
+
+ envp[i] = NULL;
+
+ environ = envp;
+ return 0;
+}