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authorTaru Karttunen <taruti@taruti.net>2011-03-30 15:46:40 +0300
committerTaru Karttunen <taruti@taruti.net>2011-03-30 15:46:40 +0300
commite5888a1ffdae813d7575f5fb02275c6bb07e5199 (patch)
treed8d51eac403f07814b9e936eed0c9a79195e2450 /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-xsys/src/libc/port/strtoull.c97
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;
+}