added ksprintf_fast(); improve later...

diff --git a/kstring.c b/kstring.c
index b2a0dab03c36f616c50aa6e5b79709134855db8e..e86c9ecae379f65e6d1d0f008fd65659efc13ed1 100644 (file)
--- a/kstring.c
+++ b/kstring.c
@@ -166,6 +166,107 @@ char *kstrnstr(const char *str, const char *pat, int n, int **_prep)
        return (char*)kmemmem(str, n, pat, strlen(pat), _prep);
 }
 
+/****************
+ * fast sprintf *
+ ****************/
+
+static inline void enlarge(kstring_t *s, int l)
+{
+       if (s->l + l + 1 >= s->m) {
+               s->m = s->l + l + 2;
+               kroundup32(s->m);
+               s->s = (char*)realloc(s->s, s->m);
+       }
+}
+
+static int get_base(int c)
+{
+       if (c == 'o') return 8;
+       if (c == 'x') return 16;
+       return 10;
+}
+
+int ksprintf_fast(kstring_t *s, const char *fmt, ...)
+{
+
+#define write_integer(_ap, _s, _type, _base) do { \
+               _type c = va_arg(_ap, _type); \
+               if (c == 0) { \
+                       enlarge(_s, 1); \
+                       _s->s[_s->l++] = '0'; \
+                       _s->s[_s->l] = 0; \
+               } else { \
+                       char buf[32]; \
+                       int l, ll; \
+                       _type x; \
+                       for (l = 0, x = c < 0? -c : c; x > 0; x /= _base) buf[l++] = "0123456789abcdef"[x%_base]; \
+                       if (c < 0) buf[l++] = '-'; \
+                       enlarge(_s, l); \
+                       for (ll = l - 1; ll >= 0; --ll) _s->s[_s->l++] = buf[ll]; \
+                       _s->s[_s->l] = 0; \
+               } \
+       } while (0)
+
+       va_list ap;
+       const char *p = fmt, *q;
+       va_start(ap, fmt);
+       while (*p) {
+               if (*p == '%') {
+                       ++p;
+                       if (*p == '%') {
+                               enlarge(s, 1);
+                               s->s[s->l++] = '%';
+                               s->s[s->l] = 0;
+                       } else if (*p == 's') { // %s
+                               char *r = va_arg(ap, char*);
+                               int l = strlen(r);
+                               enlarge(s, l);
+                               memcpy(s->s + s->l, r, l);
+                               s->l += l;
+                               s->s[s->l] = 0;
+                       } else if (*p == 'c') { // %c
+                               enlarge(s, 1);
+                               s->s[s->l++] = va_arg(ap, int);
+                               s->s[s->l] = 0;
+                       } else if (*p == 'd' || *p == 'i') { // %d or %i
+                               write_integer(ap, s, int, 10);
+                       } else if (*p == 'u' || *p == 'o' || *p == 'x') { // %u, %o or %x
+                               int base = get_base(*p);
+                               write_integer(ap, s, unsigned, base);
+                       } else if (*p == 'l') {
+                               ++p;
+                               if (*p == 'l') {
+                                       ++p;
+                                       if (*p == 'd' || *p == 'i') { // %lld or %lli
+                                               write_integer(ap, s, long long, 10);
+                                       } else if (*p == 'u' || *p == 'o' || *p == 'x') {
+                                               int base = get_base(*p);
+                                               write_integer(ap, s, unsigned long long, base);
+                                       }
+                               } else if (*p == 'd' || *p == 'i') { // %ld or %li
+                                       write_integer(ap, s, long, 10);
+                               } else if (*p == 'u' || *p == 'o' || *p == 'x') {
+                                       int base = get_base(*p);
+                                       write_integer(ap, s, unsigned long, base);
+                               }
+                       }
+                       ++p;
+               } else {
+                       q = p;
+                       while (*p && *p != '%') ++p;
+                       enlarge(s, p - q);
+                       memcpy(s->s + s->l, q, p - q);
+                       s->l += p - q;
+                       s->s[s->l] = 0;
+               }
+       }
+       va_end(ap);
+
+#undef write_integer
+
+       return 0;
+}
+
 /***********************
  * The main() function *
  ***********************/
@@ -179,6 +280,10 @@ int main()
        ks_tokaux_t aux;
        char *p;
        s = (kstring_t*)calloc(1, sizeof(kstring_t));
+       { // test ksprintf_fast()
+               long xx = -10;
+               ksprintf_fast(s, " pooiu %% %s %ld %c %x", "+++", xx, '*', 100); printf("'%s'\n", s->s); s->l = 0;
+       }
        // test ksprintf()
        ksprintf(s, " abcdefg:    %d ", 100);
        printf("'%s'\n", s->s);