move all compatibility library stuff into libgcompat/

1 files changed, 84 insertions, 0 deletions

diff --git a/libgcompat/string.c b/libgcompat/string.c
new file mode 100644
index 0000000..9a1cb60
--- /dev/null
+++ b/libgcompat/string.c
@@ -0,0 +1,84 @@
+#include <assert.h>	/* assert */
+#include <string.h>	/* memcpy, strcpy, strncat, strndup */
+
+/* "Checked" memcpy */
+void *__memcpy_chk(void *dest, const void *src, size_t len, size_t destlen)
+{
+	assert(dest != NULL);
+	assert(src != NULL);
+	assert(len <= destlen);
+	if(src < dest)
+	{
+		assert(!(src + len >= dest));
+	} else {
+		assert(!(dest + len >= src));
+	}
+	return memcpy(dest, src, len);
+}
+
+/* "Checked" strncat */
+char *__strncat_chk(char *dest, const char *src, size_t n, size_t destlen)
+{
+	assert(dest != NULL);
+	assert(src != NULL);
+	assert(n <= destlen);
+
+	return strncat(dest, src, n);
+}
+
+/* "Checked" strcat */
+char *__strcat_chk(char *dest, const char *src, size_t destlen)
+{
+	return strncat(dest, src, destlen - 1);
+}
+
+/* "Checked" strncpy */
+char *__strncpy_chk(char *dest, const char *src, size_t n, size_t destlen)
+{
+	assert(dest != NULL);
+	assert(src != NULL);
+	assert(strlen(src) < destlen);
+
+	return strncpy(dest, src, n);
+}
+
+/* "Checked" strcpy */
+char *__strcpy_chk(char *dest, const char *src, size_t destlen)
+{
+	assert(dest != NULL);
+	assert(src != NULL);
+	assert(strlen(src) < destlen);
+
+	return strcpy(dest, src);
+}
+
+/* Literally a useless __ alias. */
+char *__strndup(const char *str, size_t count)
+{
+	return strndup(str, count);
+}
+
+/* The existance of this method, and the fact it is used in real code, gives
+ * me nightmares. */
+void *rawmemchr(const void *s, int c)
+{
+	const unsigned char *haystack = s;
+	unsigned char needle = (unsigned char)c;
+	while(*haystack++ != needle);
+	return (void *)haystack;
+}
+
+extern __typeof(rawmemchr) __rawmemchr __attribute__((weak, alias("rawmemchr")));
+
+/* Another useless __ alias */
+char *__strtok_r(char *str, const char *delim, char **saveptr)
+{
+	return strtok_r(str, delim, saveptr);
+}
+
+/* The "global" definition of strsep in glibc, used when architecture dependent
+ * assembler versions aren't good enough. */
+char *__strsep_g(char **stringp, const char *delim)
+{
+	return strsep(stringp, delim);
+}