add buffer_tosa (buffer writing to auto-growing stralloc)

CHANGES

@@ -1,5 +1,6 @@
 0.29:
   save 8 bytes in taia.h for 64-bit systems
+  add buffer_tosa (buffer writing to auto-growing stralloc)
 
 0.28:
   add uint64 pack and unpack routines

buffer.h

@@ -14,9 +14,10 @@ typedef struct buffer {
   int fd;		/* passed as first argument to op */
   ssize_t (*op)();	/* use read(2) or write(2) */
   enum { NOTHING, FREE, MUNMAP } todo;
+  void* cookie;
 } buffer;
 
-#define BUFFER_INIT(op,fd,buf,len) { (buf), 0, 0, (len), (fd), (op), NOTHING }
+#define BUFFER_INIT(op,fd,buf,len) { (buf), 0, 0, (len), (fd), (op), NOTHING, NULL }
 #define BUFFER_INIT_FREE(op,fd,buf,len) { (buf), 0, 0, (len), (fd), (op), FREE }
 #define BUFFER_INIT_READ(op,fd,buf,len) BUFFER_INIT(op,fd,buf,len) /*obsolete*/
 #define BUFFER_INSIZE 8192
@@ -135,7 +136,8 @@ int buffer_get_new_token_sa_pred(buffer* b,stralloc* sa,sa_predicate p);
 
 /* make a buffer from a stralloc.
  * Do not change the stralloc after this! */
-void buffer_fromsa(buffer* b,stralloc* sa);
+void buffer_fromsa(buffer* b,stralloc* sa);	/* read from sa */
+int buffer_tosa(buffer*b,stralloc* sa);		/* write to sa, auto-growing it */
 #endif
 
 #endif

buffer/buffer_feed.c

@@ -1,11 +1,11 @@
 #include "buffer.h"
 
-extern int buffer_stubborn_read(ssize_t (*op)(),int fd,const char* buf, size_t len);
+extern int buffer_stubborn_read(ssize_t (*op)(),int fd,const char* buf, size_t len,void* cookie);
 
 int buffer_feed(buffer* b) {
   if (b->p==b->n) {
     int w;
-    if ((w=buffer_stubborn_read(b->op,b->fd,b->x,b->a))<0)
+    if ((w=buffer_stubborn_read(b->op,b->fd,b->x,b->a,b))<0)
       return -1;
     b->n=w;
     b->p=0;

buffer/buffer_flush.c

@@ -1,10 +1,10 @@
 #include "buffer.h"
 
-extern int buffer_stubborn(ssize_t (*op)(),int fd,const char* buf, size_t len);
+extern int buffer_stubborn(ssize_t (*op)(),int fd,const char* buf, size_t len,void* cookie);
 
 extern int buffer_flush(buffer* b) {
   register int p;
   if (!(p=b->p)) return 0; /* buffer already empty */
   b->p=0;
-  return buffer_stubborn(b->op,b->fd,b->x,p);
+  return buffer_stubborn(b->op,b->fd,b->x,p,b);
 }

buffer/buffer_init.c

@@ -9,4 +9,5 @@ void buffer_init(buffer* b,ssize_t (*op)(),int fd,
   b->p=0;
   b->n=0;
   b->todo=NOTHING;
+  b->cookie=0;
 }

buffer/buffer_put.c

@@ -1,13 +1,13 @@
 #include "byte.h"
 #include "buffer.h"
 
-extern int buffer_stubborn(ssize_t (*op)(),int fd,const char* buf, size_t len);
+extern int buffer_stubborn(ssize_t (*op)(),int fd,const char* buf, size_t len,void* cookie);
 
 int buffer_put(buffer* b,const char* buf,size_t len) {
   if (len>b->a-b->p) {	/* doesn't fit */
     if (buffer_flush(b)==-1) return -1;
     if (len>b->a) {
-      if (buffer_stubborn(b->op,b->fd,buf,len)<0) return -1;
+      if (buffer_stubborn(b->op,b->fd,buf,len,b)<0) return -1;
       return 0;
     }
   }

buffer/buffer_stubborn.c

@@ -1,10 +1,10 @@
 #include <errno.h>
 #include "buffer.h"
 
-int buffer_stubborn(ssize_t (*op)(),int fd,const char* buf, size_t len) {
+int buffer_stubborn(ssize_t (*op)(),int fd,const char* buf, size_t len,void* cookie) {
   int w;
   while (len) {
-    if ((w=op(fd,buf,len))<0) {
+    if ((w=op(fd,buf,len,cookie))<0) {
       if (errno == EINTR) continue;
       return -1;
     };

buffer/buffer_stubborn2.c

@@ -1,10 +1,10 @@
 #include <errno.h>
 #include "buffer.h"
 
-int buffer_stubborn_read(ssize_t (*op)(),int fd,const char* buf, size_t len) {
+int buffer_stubborn_read(ssize_t (*op)(),int fd,const char* buf, size_t len,void* cookie) {
   int w;
   for (;;) {
-    if ((w=op(fd,buf,len))<0)
+    if ((w=op(fd,buf,len,cookie))<0)
       if (errno == EINTR) continue;
     break;
   }

buffer/buffer_tosa.c

@@ -0,0 +1,27 @@
+#include "stralloc.h"
+#include "buffer.h"
+
+static ssize_t strallocwrite(int fd,char* buf,size_t len,void* myself) {
+  buffer* b=myself;
+  stralloc* sa=b->cookie;
+  sa->len+=len;
+  if (stralloc_readyplus(sa,1024)==0) return 0;
+  b->x=sa->s+sa->len;
+  b->p=0;
+  b->a=1024;
+  (void)fd;
+  (void)buf;
+  return len;
+}
+
+int buffer_tosa(buffer* b,stralloc* sa) {
+  if (stralloc_ready(sa,1024)==0) return -1;
+  b->x=sa->s;
+  b->p=0;
+  b->n=0;
+  b->a=1024;
+  b->fd=0;
+  b->op=strallocwrite;
+  b->cookie=sa;
+  return 0;
+}

t.c

@@ -41,13 +41,25 @@ int64 writecb(int64 fd,const void* buf,uint64 n) {
 }
 
 int main(int argc,char* argv[]) {
+  stralloc a;
+  buffer b;
+  int i;
+  stralloc_init(&a);
+  buffer_tosa(&b,&a);
+
+  for (i=0; i<100; ++i)
+    buffer_puts(&b,"foo bar baz!\n");
+  buffer_flush(&b);
+  buffer_putsa(buffer_1,&a);
+  buffer_flush(buffer_1);
+#if 0
   char* c=fmt_strm_alloca("foo"," bar","\n");
 
   write(1,c,strlen(c));
 
   (void)argc;
   (void)argv;
-
+#endif
 #if 0
   io_batch* b=iob_new(1234);
   int64 fd=open("t.c",0);