#include #include #include int memcmp(const void *s1, const void *s2, size_t n) { const unsigned char *c1 = s1, *c2 = s2; for (size_t i = 0; i < n; i++) { if (c1[i] != c2[i]) { if (c1[i] < c2[i]) return -1; else return 1; } } return 0; } size_t strlen(const char *s) { size_t c = 0; while (*s++) c++; return c; } int printf(const char *fmt, ...) { const char *seg = fmt; // beginning of the current segment int total = 0; va_list argp; va_start(argp, fmt); for (;;) { char c = *fmt++; switch (c) { case '\0': // TODO don't assume that stdout is @ fd 0 _syscall_write(0, seg, fmt - seg - 1, 0); return total + (fmt - seg - 1); case '%': _syscall_write(0, seg, fmt - seg - 1, 0); total += fmt - seg - 1; c = *fmt++; switch (c) { case 's': const char *s = va_arg(argp, char*); _syscall_write(0, s, strlen(s), 0); total += strlen(s); break; } seg = fmt; break; } } }