summaryrefslogtreecommitdiffstats
path: root/kernel/lib/argv_split.c
diff options
context:
space:
mode:
authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/lib/argv_split.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/lib/argv_split.c')
-rw-r--r--kernel/lib/argv_split.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/kernel/lib/argv_split.c b/kernel/lib/argv_split.c
new file mode 100644
index 000000000..e927ed0e1
--- /dev/null
+++ b/kernel/lib/argv_split.c
@@ -0,0 +1,94 @@
+/*
+ * Helper function for splitting a string into an argv-like array.
+ */
+
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+static int count_argc(const char *str)
+{
+ int count = 0;
+ bool was_space;
+
+ for (was_space = true; *str; str++) {
+ if (isspace(*str)) {
+ was_space = true;
+ } else if (was_space) {
+ was_space = false;
+ count++;
+ }
+ }
+
+ return count;
+}
+
+/**
+ * argv_free - free an argv
+ * @argv - the argument vector to be freed
+ *
+ * Frees an argv and the strings it points to.
+ */
+void argv_free(char **argv)
+{
+ argv--;
+ kfree(argv[0]);
+ kfree(argv);
+}
+EXPORT_SYMBOL(argv_free);
+
+/**
+ * argv_split - split a string at whitespace, returning an argv
+ * @gfp: the GFP mask used to allocate memory
+ * @str: the string to be split
+ * @argcp: returned argument count
+ *
+ * Returns an array of pointers to strings which are split out from
+ * @str. This is performed by strictly splitting on white-space; no
+ * quote processing is performed. Multiple whitespace characters are
+ * considered to be a single argument separator. The returned array
+ * is always NULL-terminated. Returns NULL on memory allocation
+ * failure.
+ *
+ * The source string at `str' may be undergoing concurrent alteration via
+ * userspace sysctl activity (at least). The argv_split() implementation
+ * attempts to handle this gracefully by taking a local copy to work on.
+ */
+char **argv_split(gfp_t gfp, const char *str, int *argcp)
+{
+ char *argv_str;
+ bool was_space;
+ char **argv, **argv_ret;
+ int argc;
+
+ argv_str = kstrndup(str, KMALLOC_MAX_SIZE - 1, gfp);
+ if (!argv_str)
+ return NULL;
+
+ argc = count_argc(argv_str);
+ argv = kmalloc(sizeof(*argv) * (argc + 2), gfp);
+ if (!argv) {
+ kfree(argv_str);
+ return NULL;
+ }
+
+ *argv = argv_str;
+ argv_ret = ++argv;
+ for (was_space = true; *argv_str; argv_str++) {
+ if (isspace(*argv_str)) {
+ was_space = true;
+ *argv_str = 0;
+ } else if (was_space) {
+ was_space = false;
+ *argv++ = argv_str;
+ }
+ }
+ *argv = NULL;
+
+ if (argcp)
+ *argcp = argc;
+ return argv_ret;
+}
+EXPORT_SYMBOL(argv_split);