================ String Functions ================ .. include:: check.rst --------------- Source location --------------- - The main source for string functions is located at: ``libc/src/string``. - The source for string conversion functions is located at: ``libc/src/stdlib`` and ``libc/src/__support``. - The tests are located at: ``libc/test/src/string``, ``libc/test/src/stdlib``, and ``libc/test/src/__support`` respectively. --------------------- Implementation Status --------------------- Primary memory functions ======================== .. TODO(gchatelet): add details about the memory functions. ============= ========= Function Name Available ============= ========= bzero |check| bcmp |check| bcopy |check| memcpy |check| memset |check| memcmp |check| memmove |check| ============= ========= Other Raw Memory Functions ========================== ============= ========= Function Name Available ============= ========= memchr |check| memrchr |check| memccpy |check| mempcpy |check| ============= ========= String Memory Functions ======================= ============= ========= Function Name Available ============= ========= stpcpy |check| stpncpy |check| strcpy |check| strncpy |check| strcat |check| strncat |check| strdup |check| strndup |check| ============= ========= String Examination Functions ============================ ============= ========= Function Name Available ============= ========= strlen |check| strnlen |check| strcmp |check| strncmp |check| strchr |check| strrchr |check| strspn |check| strcspn |check| strpbrk |check| strstr |check| strtok |check| strtok_r |check| ============= ========= String Conversion Functions ============================ These functions are not in strings.h, but are still primarily string functions, and are therefore tracked along with the rest of the string functions. The String to float functions were implemented using the Eisel-Lemire algorithm (read more about the algorithm here: `The Eisel-Lemire ParseNumberF64 Algorithm `_). This improved the performance of string to float and double, and allowed it to complete this comprehensive test 15% faster than glibc: `Parse Number FXX Test Data `_. The test was done with LLVM-libc built on 2022-04-14 and Debian GLibc version 2.33-6. The targets ``libc_str_to_float_comparison_test`` and ``libc_system_str_to_float_comparison_test`` were built and run on the test data 10 times each, skipping the first run since it was an outlier. ============= ========= Function Name Available ============= ========= atof |check| atoi |check| atol |check| atoll |check| strtol |check| strtoll |check| strtoul |check| strtoull |check| strtof |check| strtod |check| strtold |check| strtoimax |check| strtoumax |check| ============= ========= String Error Functions ====================== ============= ========= Function Name Available ============= ========= strerror |check| strerror_r |check| ============= ========= Localized String Functions ========================== These functions require locale.h, and will be finished when locale support is implemented in LLVM-libc. ============= ========= Function Name Available ============= ========= strcoll Partially strxfrm Partially ============= ========= --------------------------- \_s String Functions --------------------------- Many String functions have an equivalent _s version, which is intended to be more secure and safe than the previous standard. These functions add runtime error detection and overflow protection. While they can be seen as an improvement, adoption remains relatively low among users. In addition, they are being considered for removal, see `Field Experience With Annex K — Bounds Checking Interfaces `_. For these reasons, there is no ongoing work to implement them.