Fix the crashes found by the fuzzer so far.

I really need to think of a better way to store those crash inputs.

FossilOrigin-Name: a8b84fbc85ec0b472aca930d2d0af27949b39940317114cc37d37044bf1975d5

1 files changed, 6 insertions, 2 deletions

diff --git a/src/lib/string.c b/src/lib/string.c
index 4101b80..0c01fca 100644
--- a/src/lib/string.c
+++ b/src/lib/string.c
@@ -104,6 +104,10 @@ string_char(struct string *string, size_t offset)
 	uint32_t c;
 	size_t len, i;
 
+	assert(offset <= string->bytes);
+	if(offset == string->bytes)
+		return INVALID_CHAR;
+
 	c = 0;
 	len = char_length(string, offset);
 	switch(char_length(string, offset)){
@@ -134,8 +138,8 @@ char_length(struct string *string, size_t offset)
 {
 	uint8_t b;
 
-	if(offset >= string->bytes)
-		return 0;
+	assert(offset < string->bytes);
+
 	b = string->utf8[offset];
 	assert(!((b & 0xC0) == 0x80));