| # Starboard and C99 |
| |
| ## Background |
| |
| Historically Starboard did not allow usage of standard C symbols in order to |
| isolate Cobalt from non-compliant libc implementations and to provide a single, |
| consistent behavior at the Starboard API layer. |
| |
| ## C99 Usage Rationale |
| 1. Inconsistencies in the libc libraries are rare and all third party libraries |
| need to be ported to the Starboard API. This can be a significant maintenance |
| cost as the dependencies need to be periodically rebased. |
| |
| 2. Even with all the efforts to use POEM headers from the |
| [starboard/client_porting](../../starboard/client_porting) directory many |
| non-Evergreen platforms still have a lot of direct system dependencies. These |
| dependencies do not exist for Evergreen platforms as Cobalt is statically |
| linked with the [musl](../../third_party/musl/BUILD.gn) libc library. |
| |
| 3. Starting with Starboard 13 a limited set of C99 symbols will be allowed. |
| This set will expand gradually while the corresponding Starboard APIs will be |
| deprecated and eventually removed. |
| |
| ## List of Allowed C99 Symbols |
| ### <ctype.h> |
| * isalnum |
| * isdigit |
| * isspace |
| * isupper |
| * isxdigit |
| * tolower |
| * toupper |
| ### <math.h> |
| * acos |
| * acosf |
| * asin |
| * asinf |
| * atan |
| * atan2 |
| * atan2f |
| * atanf |
| * cbrt |
| * cbrtf |
| * ceil |
| * ceilf |
| * cos |
| * cosf |
| * div |
| * erf |
| * erff |
| * exp |
| * expf |
| * exp2f |
| * fabs |
| * floor |
| * floorf |
| * fmod |
| * fmodf |
| * frexp |
| * isfinite |
| * isnan |
| * labs |
| * llround |
| * llroundf |
| * log |
| * log10 |
| * log10f |
| * log2 |
| * log2f |
| * ldexp |
| * lrint |
| * lrintf |
| * modf |
| * nearbyint |
| * nearbyintf |
| * nextafter |
| * nextafterf |
| * pow |
| * powf |
| * round |
| * roundf |
| * scalbn |
| * sin |
| * sinf |
| * sqrt |
| * sqrtf |
| * tan |
| * tanf |
| * trunc |
| * truncf |
| ### <stdlib.h> |
| * abs |
| * atoi |
| * atol |
| * bsearch |
| * strtof |
| * strtod |
| * strtol |
| * strtoll |
| * strtoul |
| * strtoull |
| * qsort |
| ### <string.h> |
| * memchr |
| * memcmp |
| * memcpy |
| * memmove |
| * memset |
| * strcat |
| * strchr |
| * strcmp |
| * strcpy |
| * strcspn |
| * strlen |
| * strncmp |
| * strncat |
| * strncpy |
| * strrchr |
| * strstr |
| * strspn |
| ### <tgmath.h> |
| * ceill |
| * logl |
| ### <wchar.h> |
| * wcscat |
| * wcschr |
| * wcslen |
| * wmemchr |
| * wmemcmp |
| * wmemcpy |
| * wmemmove |
| * wmemset |
| * wcsncmp |
