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-rw-r--r--libc-top-half/musl/src/string/strverscmp.c34
1 files changed, 34 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/string/strverscmp.c b/libc-top-half/musl/src/string/strverscmp.c
new file mode 100644
index 0000000..4daf276
--- /dev/null
+++ b/libc-top-half/musl/src/string/strverscmp.c
@@ -0,0 +1,34 @@
+#define _GNU_SOURCE
+#include <ctype.h>
+#include <string.h>
+
+int strverscmp(const char *l0, const char *r0)
+{
+ const unsigned char *l = (const void *)l0;
+ const unsigned char *r = (const void *)r0;
+ size_t i, dp, j;
+ int z = 1;
+
+ /* Find maximal matching prefix and track its maximal digit
+ * suffix and whether those digits are all zeros. */
+ for (dp=i=0; l[i]==r[i]; i++) {
+ int c = l[i];
+ if (!c) return 0;
+ if (!isdigit(c)) dp=i+1, z=1;
+ else if (c!='0') z=0;
+ }
+
+ if (l[dp]!='0' && r[dp]!='0') {
+ /* If we're not looking at a digit sequence that began
+ * with a zero, longest digit string is greater. */
+ for (j=i; isdigit(l[j]); j++)
+ if (!isdigit(r[j])) return 1;
+ if (isdigit(r[j])) return -1;
+ } else if (z && dp<i && (isdigit(l[i]) || isdigit(r[i]))) {
+ /* Otherwise, if common prefix of digit sequence is
+ * all zeros, digits order less than non-digits. */
+ return (unsigned char)(l[i]-'0') - (unsigned char)(r[i]-'0');
+ }
+
+ return l[i] - r[i];
+}