[libc] Fix strcmp()/strncmp() to return proper values
Fix strcmp() and strncmp() to return proper standard positive/negative
values for unequal strings. Current implementation is backwards
(i.e. the functions are returning negative when should be positive and
vice-versa).
Currently all consumers of these functions only check the return value
for ==0 or !=0 and so we can safely change the implementation without
breaking things.
Signed-off-by: Aaron Young <Aaron.Young@oracle.com>
Modified-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[libc] Avoid implicit assumptions about potentially-optimised memcpy()
Do not assume that an architecture-specific optimised memcpy() will
have the same properties as generic_memcpy() in terms of handling
overlapping regions.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The implementation of strtoul() has a partially unknown provenance.
Rewrite this code to avoid potential licensing uncertainty.
Since we now use -ffunction-sections, there is no need to place
strtoull() in a separate file from strtoul().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some of the C library string functions have an unknown provenance.
Reimplement all such functions to avoid potential licensing
uncertainty.
Remove the inline-assembler versions of strlen(), memswap(), and
strncmp(); these save a minimal amount of space (around 40 bytes in
total) and are not performance-critical.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[libc] Prevent strndup() from reading beyond the end of the string
strndup() may be called on a string which is not NUL-terminated. Use
strnlen() instead of strlen() to ensure that we do not read beyond the
end of such a string.
Add self-tests for strndup(), including a test case with an
unterminated string.
Originally-fixed-by: Marin Hannache <git@mareo.fr>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Aaron Young