diff options
author | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
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committer | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
commit | e5888a1ffdae813d7575f5fb02275c6bb07e5199 (patch) | |
tree | d8d51eac403f07814b9e936eed0c9a79195e2450 /sys/src/libc/port/strtoull.c |
Import sources from 2011-03-30 iso image
Diffstat (limited to 'sys/src/libc/port/strtoull.c')
-rwxr-xr-x | sys/src/libc/port/strtoull.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/sys/src/libc/port/strtoull.c b/sys/src/libc/port/strtoull.c new file mode 100755 index 000000000..85ab7c5fc --- /dev/null +++ b/sys/src/libc/port/strtoull.c @@ -0,0 +1,97 @@ +#include <u.h> +#include <libc.h> + +#define UVLONG_MAX (1LL<<63) + +uvlong +strtoull(char *nptr, char **endptr, int base) +{ + char *p; + uvlong n, nn, m; + int c, ovfl, v, neg, ndig; + + p = nptr; + neg = 0; + n = 0; + ndig = 0; + ovfl = 0; + + /* + * White space + */ + for(;; p++) { + switch(*p) { + case ' ': + case '\t': + case '\n': + case '\f': + case '\r': + case '\v': + continue; + } + break; + } + + /* + * Sign + */ + if(*p == '-' || *p == '+') + if(*p++ == '-') + neg = 1; + + /* + * Base + */ + if(base == 0) { + base = 10; + if(*p == '0') { + base = 8; + if(p[1] == 'x' || p[1] == 'X'){ + p += 2; + base = 16; + } + } + } else + if(base == 16 && *p == '0') { + if(p[1] == 'x' || p[1] == 'X') + p += 2; + } else + if(base < 0 || 36 < base) + goto Return; + + /* + * Non-empty sequence of digits + */ + m = UVLONG_MAX/base; + for(;; p++,ndig++) { + c = *p; + v = base; + if('0' <= c && c <= '9') + v = c - '0'; + else + if('a' <= c && c <= 'z') + v = c - 'a' + 10; + else + if('A' <= c && c <= 'Z') + v = c - 'A' + 10; + if(v >= base) + break; + if(n > m) + ovfl = 1; + nn = n*base + v; + if(nn < n) + ovfl = 1; + n = nn; + } + +Return: + if(ndig == 0) + p = nptr; + if(endptr) + *endptr = p; + if(ovfl) + return UVLONG_MAX; + if(neg) + return -n; + return n; +} |