don't use sprintf for rendering numbers

include/psyc/lib.h

@@ -15,4 +15,8 @@
 void * memmem(const void *l, size_t l_len, const void *s, size_t s_len);
 #endif
 
+#if !defined(_GNU_SOURCE) && !defined(__FBSDID)
+int itoa(int number, char* out, int base);
+#endif
+
 #endif // PSYC_LIB_H

src/Makefile

@@ -2,8 +2,8 @@ CFLAGS=-I../include -DDEBUG=2 -DPSYC_COMPILE_LIBRARY -g -O0 -Wall
 CC=cc
 # CC=clang
 
-S=psyc.c parser.c match.c render.c memmem.c variable.c
-O=psyc.o parser.o match.o render.o memmem.o variable.o
+S=psyc.c parser.c match.c render.c memmem.c itoa.c variable.c
+O=psyc.o parser.o match.o render.o memmem.o itoa.o variable.o
 
 default: 
 	@/bin/echo -e "Usage:\n\tmake diet - compile with diet libc\n\tmake lib  - compile with normal gnu libc"
@@ -19,6 +19,9 @@ lib: $S
 match: match.c
 	${CC} -o $@ -DDEBUG=4 -DCMDTOOL -DTEST $<
 
+itoa: itoa.c
+	${CC} -o $@ -DDEBUG=4 -DCMDTOOL -DTEST -O0 $<
+
 it: match
 
 clean:

src/itoa.c

@@ -0,0 +1,85 @@
+#define ALPHANUMS "zyxwvutsrqponmlkjihgfedcba9876543210123456789abcdefghijklmnopqrstuvwxyz"
+
+/** converts an integer to a string, using a base of 10 by default.
+ *
+ * if you NULL out the output buffer it will return the expected
+ * output string length anyway.
+ */
+int itoa(int number, char* out, int base) {
+	int t, count;
+	char *p, *q;
+	char c;
+
+	p = q = out;
+	if (base < 2 || base > 36) base = 10;
+
+	do {
+		t = number;
+		number /= base;
+		if (out) *p = ALPHANUMS[t+35 - number*base];
+		p++;
+	} while (number);
+
+	if (t < 0) {
+	     if (out) *p = '-';
+	     p++;
+	}
+	count = p-out;
+	if (out) {
+		*p-- = '\0';
+		while(q < p) {
+			c = *p;
+			*p-- = *q;
+			*q++ = c;
+		}
+	}
+	return count;
+}
+
+/* This little test program shows that itoa() is roughly 3 times faster
+ * than sprintf  --lynX
+ */
+#ifdef CMDTOOL
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+int main(int argc, char **argv) {
+	char out[4404];
+	int in[44];
+	int c, i, j;
+
+        if (argc < 3 || argc > sizeof(in)) {
+                printf("Usage: %s <times> <numbers>+\n\nExample: %s 999999 123 234 345 -49 -21892\n", argv[0], argv[0]);
+                return -1;
+        }
+	for (j=argc-1; j; j--) {
+//		printf("Looking at arg #%d: %s\n", j, argv[j]);
+		in[j] = atoi(argv[j]);
+//		printf("Got %d: %d\n", j, in[j]);
+	}
+	for (i=in[1]; i; i--) {
+		c = 0;
+		for (j=argc-1; j>1; j--) {
+# if 0
+			// use good old sprintf
+			c += sprintf(&out[c], " %d", in[j]);
+# else
+#  if 1
+			// use the itoa implementation
+			out[c++] = ' ';
+			c += itoa(in[j], &out[c], 10);
+#  else
+			// just count the needed space
+			c += itoa(in[j], NULL, 10) + 1;
+#  endif
+# endif
+		}
+	}
+        printf("%d times, %d count, buffer len: %d, buffer: %s\n",
+	    in[1], c, strlen(out), "<omitted>");	// out
+	return 0;
+}
+
+#endif

src/render.c

@@ -11,7 +11,8 @@ inline int PSYC_renderModifier(PSYC_Modifier *m, char *buffer)
 	if (m->flag == PSYC_MODIFIER_NEED_LENGTH)
 	{
 		buffer[cur++] = ' ';
-		cur += sprintf(buffer + cur, "%ld", m->value.length);
+//		cur += sprintf(buffer + cur, "%ld", m->value.length);
+		cur += itoa(m->value.length, buffer + cur, 10);
 	}
 	memcpy(buffer + cur, m->value.ptr, m->value.length);
 	cur += m->value.length;
@@ -30,8 +31,10 @@ PSYC_RenderRC PSYC_render(PSYC_Packet *packet, char *buffer, size_t buflen)
 	for (i = 0; i < packet->routing.lines; i++)
 		cur += PSYC_renderModifier(packet->routing.modifiers[i], buffer + cur);
 
-	if (packet->flag == PSYC_PACKET_NEED_LENGTH)
-		cur += sprintf(buffer + cur, "%ld", packet->contentLength);
+	if (packet->flag == PSYC_PACKET_NEED_LENGTH) {
+//		cur += sprintf(buffer + cur, "%ld", packet->contentLength);
+		cur += itoa(packet->contentLength, buffer + cur, 10);
+	}
 
 	buffer[cur++] = '\n';