add fmt_pad and fmt_fill.

Makefile

@@ -4,7 +4,7 @@ VPATH=str:byte:fmt:scan:uint:open:stralloc:unix:socket:buffer:mmap
 
 CC=egcc
 #CFLAGS=-I. -pipe -Wall -Os -march=pentiumpro -fomit-frame-pointer -fschedule-insns2 -Wall
-CFLAGS=-I. -I../dietlibc/include -pipe -Wall -Os -march=athlon -mcpu=athlon -malign-functions=2 -fomit-frame-pointer -fschedule-insns2 -g
+CFLAGS=-I. -I../dietlibc/include -pipe -Wall -Os -march=athlon -mcpu=athlon -malign-functions=2 -fschedule-insns2 -g
 #CFLAGS=-I../dietlibc/include -I. -pipe -Wall -Os -march=pentiumpro -mcpu=athlon -fomit-frame-pointer -fschedule-insns2 -Wall
 #CFLAGS=-I../dietlibc/include -pipe -Os -march=pentiumpro -mcpu=pentiumpro -fomit-frame-pointer -fschedule-insns2 -Wall
 

fmt.h

@@ -58,4 +58,16 @@ unsigned int fmt_str(char *dest,const char *src) __THROW;
  * return number of copied bytes. */
 unsigned int fmt_strn(char *dest,const char *src,unsigned int limit) __THROW;
 
+/* "foo" -> "  foo"
+ * write padlen-srclen spaces, if that is >= 0.  Then copy srclen
+ * characters from src.  Truncate only if total length is larger than
+ * maxlen.  Return number of characters written. */
+unsigned int fmt_pad(char* dest,const char* src,unsigned int srclen,unsigned int padlen,unsigned int maxlen) __THROW;
+
+/* "foo" -> "foo  "
+ * write padlen-srclen spaces, if that is >= 0.  Then copy srclen
+ * characters from src.  Truncate only if total length is larger than
+ * maxlen.  Return number of characters written. */
+unsigned int fmt_fill(char* dest,const char* src,unsigned int srclen,unsigned int padlen,unsigned int maxlen) __THROW;
+
 #endif

fmt/fmt_fill.c

@@ -0,0 +1,20 @@
+#include "fmt.h"
+
+/* "foo" -> "foo  "
+ *  Copy srclen characters from src.  write padlen-srclen spaces, if
+ *  that is >= 0.  Truncate only if total length is larger than maxlen.
+ *  Return number of characters written. */
+unsigned int fmt_fill(char* dest,const char* src,unsigned int srclen,unsigned int padlen,unsigned int maxlen) {
+  int todo;
+  char* olddest=dest;
+  char* max=dest+maxlen;
+  for (todo=srclen; todo>0; --todo) {
+    if (dest>max) break;
+    *dest=*src; ++dest; ++src;
+  }
+  for (todo=padlen-srclen; todo>0; --todo) {
+    if (dest>max) break;
+    *dest=' '; ++dest;
+  }
+  return dest-olddest;
+}

fmt/fmt_pad.c

@@ -0,0 +1,20 @@
+#include "fmt.h"
+
+/* "foo" -> "  foo"
+ *  write padlen-srclen spaces, if that is >= 0.  Then copy srclen
+ *  characters from src.  Truncate only if total length is larger than
+ *  maxlen.  Return number of characters written. */
+unsigned int fmt_pad(char* dest,const char* src,unsigned int srclen,unsigned int padlen,unsigned int maxlen) {
+  int todo;
+  char* olddest=dest;
+  char* max=dest+maxlen;
+  for (todo=padlen-srclen; todo>0; --todo) {
+    if (dest>max) break;
+    *dest=' '; ++dest;
+  }
+  for (todo=srclen; todo>0; --todo) {
+    if (dest>max) break;
+    *dest=*src; ++dest; ++src;
+  }
+  return dest-olddest;
+}

t.c

@@ -14,9 +14,14 @@
      __asm__ __volatile__ ("rdtsc" : "=a" (low) : : "edx")
 
 int main(int argc,char* argv[]) {
+  char buf[100];
+  buf[fmt_fill(buf,"foobarbaz",3,5,100)]=0;
+  printf("\"%s\"\n",buf);
+#if 0
   unsigned long len;
   char *c=mmap_read("/etc/passwd",&len);
   printf("got map %p of len %lu\n",c,len);
+#endif
 #if 0
   char c;
   printf("%d\n",buffer_getc(buffer_0,&c));