diff options
Diffstat (limited to 'src/common/libc/string.c')
-rw-r--r-- | src/common/libc/string.c | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/src/common/libc/string.c b/src/common/libc/string.c new file mode 100644 index 0000000..f6c27b4 --- /dev/null +++ b/src/common/libc/string.c @@ -0,0 +1,126 @@ +#include <string.h> +#include <malloc.h> + + +size_t strlen(const char* str) { + size_t ret = 0; + while (str[ret] != 0) + ret++; + return ret; +} + +char *strchr(const char *str, char c) { + do { + if (*str == c) return (char*)str; + } while (*(str++)); + return NULL; +} + +char *strrchr(const char *str, char c) { + char* ret = NULL; + do { + if (*str == c) ret = (char*)str; + } while (*(str++)); + return ret; +} + +char *strcpy(char *dest, const char *src) { + memcpy(dest, src, strlen(src) + 1); + return (char*)dest; +} + +char *strncpy(char *dest, const char *src, size_t n) { + size_t x = strlen(src + 1); + if (n < x) x = n; + memcpy(dest, src, x); + if (n > x) memset(dest + n, 0, n - x); + return (char*)dest; +} + +char *strcat(char *dest, const char *src) { + char *dest2 = dest; + dest2 += strlen(dest) - 1; + while (*src) { + *dest2 = *src; + src++; + dest2++; + } + *dest2 = 0; + return dest; +} + +int strcmp(const char *s1, const char *s2) { + while ((*s1) && (*s1 == *s2)) { + s1++; + s2++; + } + return (*(unsigned char*)s1 - *(unsigned char*)s2); +} + +int strncmp(const char *s1, const char *s2, size_t n) { + size_t i = 0; + while ((*s1) && (*s1 == *s2) && i != n) { + s1++; + s2++; + i++; + } + return (*(unsigned char*)s1 - *(unsigned char*)s2); +} + +void *memcpy(void *vd, const void *vs, size_t count) { + uint8_t *dest = (uint8_t*)vd, *src = (uint8_t*)vs; + size_t f = count % 4, n = count / 4, i; + const uint32_t* s = (uint32_t*)src; + uint32_t* d = (uint32_t*)dest; + for (i = 0; i < n; i++) { + d[i] = s[i]; + } + if (f != 0) { + for (i = count - f; i < count; i++) { + dest[i] = src[i]; + } + } + return vd; +} + +void *memmove(void *vd, const void *vs, size_t count) { + uint8_t *dest = (uint8_t*)vd, *src = (uint8_t*)vs; + + if (vd < vs) { + for (size_t i = 0; i < count; i++) + dest[i] = src[i]; + } else { + for (size_t i = 0; i < count; i++) + dest[count - i] = src[count - i]; + } + return vd; +} + +int memcmp(const void *va, const void *vb, size_t count) { + uint8_t *a = (uint8_t*)va; + uint8_t *b = (uint8_t*)vb; + for (size_t i = 0; i < count; i++) { + if (a[i] != b[i]) return (int)a[i] - (int)b[i]; + } + return 0; +} + +void *memset(void *dest, int val, size_t count) { + uint8_t *dest_c = (uint8_t*)dest; + for (size_t i = 0; i < count; i++) { + dest_c[i] = val; + } + return dest; +} + +char *strdup(const char* str) { + int len = strlen(str) + 1; + + char* ret = (char*)malloc(len); + if (ret == 0) return 0; + + memcpy(ret, str, len); + return ret; +} + +/* vim: set ts=4 sw=4 tw=0 noet :*/ |