tools lib: Move argv_{split,free} from tools/perf/util/

[sfrench/cifs-2.6.git] / tools / lib / argv_split.c

diff --git a/tools/lib/argv_split.c b/tools/lib/argv_split.c
new file mode 100644 (file)
index 0000000..0a58ccf
--- /dev/null
+++ b/tools/lib/argv_split.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Helper function for splitting a string into an argv-like array.
+ */
+
+#include <stdlib.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+
+static const char *skip_arg(const char *cp)
+{
+       while (*cp && !isspace(*cp))
+               cp++;
+
+       return cp;
+}
+
+static int count_argc(const char *str)
+{
+       int count = 0;
+
+       while (*str) {
+               str = skip_spaces(str);
+               if (*str) {
+                       count++;
+                       str = skip_arg(str);
+               }
+       }
+
+       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)
+{
+       char **p;
+       for (p = argv; *p; p++) {
+               free(*p);
+               *p = NULL;
+       }
+
+       free(argv);
+}
+
+/**
+ * argv_split - split a string at whitespace, returning an argv
+ * @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.
+ */
+char **argv_split(const char *str, int *argcp)
+{
+       int argc = count_argc(str);
+       char **argv = calloc(argc + 1, sizeof(*argv));
+       char **argvp;
+
+       if (argv == NULL)
+               goto out;
+
+       if (argcp)
+               *argcp = argc;
+
+       argvp = argv;
+
+       while (*str) {
+               str = skip_spaces(str);
+
+               if (*str) {
+                       const char *p = str;
+                       char *t;
+
+                       str = skip_arg(str);
+
+                       t = strndup(p, str-p);
+                       if (t == NULL)
+                               goto fail;
+                       *argvp++ = t;
+               }
+       }
+       *argvp = NULL;
+
+out:
+       return argv;
+
+fail:
+       argv_free(argv);
+       return NULL;
+}