X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=rpikern;a=blobdiff_plain;f=src%2Flibc%2Fstdlib.c;fp=src%2Flibc%2Fstdlib.c;h=386cae7ca6fbb4cbe44b9372467bb84710f6d10c;hp=0000000000000000000000000000000000000000;hb=32ccc707bc0821d7ff4248fe9f58e92e9c6ebef9;hpb=203b43a75a028e9238307bd6e73768eb8e942071 diff --git a/src/libc/stdlib.c b/src/libc/stdlib.c new file mode 100644 index 0000000..386cae7 --- /dev/null +++ b/src/libc/stdlib.c @@ -0,0 +1,249 @@ +#include +#include +#include +#include +#include +#include + +int atoi(const char *str) +{ + return strtol(str, 0, 10); +} + +long atol(const char *str) +{ + return strtol(str, 0, 10); +} + +long strtol(const char *str, char **endp, int base) +{ + long acc = 0; + int sign = 1; + int valid = 0; + const char *start = str; + + while(isspace(*str)) str++; + + if(base == 0) { + if(str[0] == '0') { + if(str[1] == 'x' || str[1] == 'X') { + base = 16; + } else { + base = 8; + } + } else { + base = 10; + } + } + + if(*str == '+') { + str++; + } else if(*str == '-') { + sign = -1; + str++; + } + + while(*str) { + long val = LONG_MAX; + char c = tolower(*str); + + if(isdigit(c)) { + val = *str - '0'; + } else if(c >= 'a' && c <= 'f') { + val = 10 + c - 'a'; + } else { + break; + } + if(val >= base) { + break; + } + valid = 1; + + acc = acc * base + val; + str++; + } + + if(endp) { + *endp = (char*)(valid ? str : start); + } + + return sign > 0 ? acc : -acc; +} + +void itoa(int val, char *buf, int base) +{ + static char rbuf[16]; + char *ptr = rbuf; + int neg = 0; + + if(val < 0) { + neg = 1; + val = -val; + } + + if(val == 0) { + *ptr++ = '0'; + } + + while(val) { + int digit = val % base; + *ptr++ = digit < 10 ? (digit + '0') : (digit - 10 + 'a'); + val /= base; + } + + if(neg) { + *ptr++ = '-'; + } + + ptr--; + + while(ptr >= rbuf) { + *buf++ = *ptr--; + } + *buf = 0; +} + +void utoa(unsigned int val, char *buf, int base) +{ + static char rbuf[16]; + char *ptr = rbuf; + + if(val == 0) { + *ptr++ = '0'; + } + + while(val) { + unsigned int digit = val % base; + *ptr++ = digit < 10 ? (digit + '0') : (digit - 10 + 'a'); + val /= base; + } + + ptr--; + + while(ptr >= rbuf) { + *buf++ = *ptr--; + } + *buf = 0; +} + +double atof(const char *str) +{ + return strtod(str, 0); +} + + +double strtod(const char *str, char **endp) +{ + char *ep; + const char *start = str; + int valid = 0; + long ival = 0, dval = 0; + int ddig = 0; + double res; + + /* integer part */ + ival = strtol(str, &ep, 10); + if(ep == str && *str != '.') { + if(endp) *endp = (char*)str; + return 0.0; + } + if(ep != str) valid = 1; + str = *ep == '.' ? ep + 1 : ep; + if(!isdigit(*str)) { + goto done; + } + valid = 1; + + dval = strtol(str, &ep, 10); + assert(dval >= 0); + ddig = ep - str; + str = ep; + +done: + if(*endp) { + *endp = (char*)(valid ? str : start); + } + + res = (double)ival; + if(ddig) { + double d = (double)dval; + while(ddig-- > 0) { + d /= 10.0; + } + res += d; + } + return res; +} + +void abort(void) +{ + panic("Aborted\n"); +} + +#define QSORT_THRESHOLD 4 +#define ITEM(idx) ((char*)arr + (idx) * itemsz) + +#define SWAP(p, q) \ + do { \ + int nn = itemsz; \ + char *pp = (p); \ + char *qq = (q); \ + do { \ + char tmp = *pp; \ + *pp++ = *qq; \ + *qq++ = tmp; \ + } while(--nn > 0); \ + } while(0) + +static void ins_sort(void *arr, size_t count, size_t itemsz, int (*cmp)(const void*, const void*)) +{ + int i; + char *it, *a, *b; + + if(count <= 1) return; + + it = (char*)arr + itemsz; + for(i=1; i (char*)arr && cmp(a, (b = a - itemsz)) < 0) { + SWAP(a, b); + a -= itemsz; + } + } +} + +void qsort(void *arr, size_t count, size_t itemsz, int (*cmp)(const void*, const void*)) +{ + char *ma, *mb, *mc, *left, *right; + size_t sepidx, nleft, nright; + + if(count <= 1) return; + + if(count < QSORT_THRESHOLD) { + ins_sort(arr, count, itemsz, cmp); + return; + } + + ma = arr; + mb = ITEM(count / 2); + mc = ITEM(count - 1); + if(cmp(ma, mb) < 0) SWAP(ma, mb); + if(cmp(mc, ma) < 0) SWAP(mc, ma); + + left = ma + itemsz; + right = mc - itemsz; + for(;;) { + while(cmp(left, ma) < 0) left += itemsz; + while(cmp(ma, right) < 0) right -= itemsz; + if(left >= right) break; + SWAP(left, right); + } + SWAP(ma, right); + sepidx = (right - (char*)arr) / itemsz; + nleft = sepidx; + nright = count - nleft - 1; + + qsort(ma, nleft, itemsz, cmp); + qsort(right + itemsz, nright, itemsz, cmp); +}