X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;ds=inline;f=ucw%2Ffb-multi.c;h=097804c128ccb5a6900903ee71ab1148f96d3d37;hb=bc2bbfcbe76e78db9cde27455ddbcfe1ddcc61d6;hp=8071aa0cbed0e5cf70d6499066a16acb29b56580;hpb=9fa0d3b00b6e436831d37ff6257a6ee8b222fa8e;p=libucw.git

diff --git a/ucw/fb-multi.c b/ucw/fb-multi.c
index 8071aa0c..097804c1 100644
--- a/ucw/fb-multi.c
+++ b/ucw/fb-multi.c
@@ -21,257 +21,226 @@ struct fb_multi {
   struct mempool *mp;
   struct subbuf *cur;
   ucw_off_t len;
-  clist *subbufs;
+  clist subbufs;
 };
 
 #define FB_MULTI(f) ((struct fb_multi *)(f))
 
 struct subbuf {
   cnode n;
-  ucw_off_t begin, end;
-  int allow_close;
+  ucw_off_t begin, end, offset;
   struct fastbuf *fb;
 };
 
 static void
-fbmulti_subbuf_get_end(struct subbuf *s)
+fbmulti_get_ptrs(struct fastbuf *f)
 {
-  if (s->fb->seek)
-    {
-      bseek(s->fb, 0, SEEK_END);
-      s->end = s->begin + btell(s->fb);
-    }
+  struct subbuf *sb = FB_MULTI(f)->cur;
+  struct fastbuf *ff = sb->fb;
+
+  f->buffer = ff->buffer;
+  f->bptr = ff->bptr;
+  f->bstop = ff->bstop;
+  f->bufend = ff->bufend;
+  f->pos = sb->begin + (ff->pos - sb->offset);
+}
+
+static void
+fbmulti_set_ptrs(struct fastbuf *f)
+{
+  FB_MULTI(f)->cur->fb->bptr = f->bptr;
 }
 
 static int
 fbmulti_subbuf_next(struct fastbuf *f)
 {
-  struct subbuf *next = clist_next(FB_MULTI(f)->subbufs, &FB_MULTI(f)->cur->n);
-  if (next == NULL)
+  struct subbuf *cur = FB_MULTI(f)->cur;
+  struct subbuf *next = clist_next(&FB_MULTI(f)->subbufs, &cur->n);
+  if (!next)
     return 0;
-  
-  if (f->seek)
+
+  // Get the end of current buf if not known yet
+  if (!f->seek && !next->begin)
+    next->begin = cur->end = f->pos;
+
+  // Set the beginning of the next buf
+  if (next->fb->seek)
     {
       bsetpos(next->fb, 0);
-      next->begin = FB_MULTI(f)->cur->end;
+      next->offset = 0;
+    }
+  else
+    {
+      ASSERT(!f->seek);
+      next->offset = btell(next->fb);
     }
 
+  // Set the pointers
   FB_MULTI(f)->cur = next;
+  fbmulti_get_ptrs(f);
+
+  return 1;
+}
+
+static int
+fbmulti_subbuf_prev(struct fastbuf *f)
+{
+  // Called only when seeking, assuming everything seekable
+  struct subbuf *prev = clist_prev(&FB_MULTI(f)->subbufs, &FB_MULTI(f)->cur->n);
+  ASSERT(prev);
+
+  // Set pos to beginning, flush offset
+  bsetpos(prev->fb, 0);
+  prev->offset = 0;
+
+  // Set the pointers
+  FB_MULTI(f)->cur = prev;
+  fbmulti_get_ptrs(f);
+
   return 1;
 }
 
 static int
 fbmulti_refill(struct fastbuf *f)
 {
-  if (f->bufend == f->bstop)
-    f->bptr = f->bstop = f->buffer;
+  fbmulti_set_ptrs(f);
 
-  uns len = bread(FB_MULTI(f)->cur->fb, f->bstop, (f->bufend - f->bstop));
-  f->bstop += len;
-  f->pos += len;
+  // Refill the subbuf
+  uint len = FB_MULTI(f)->cur->fb->refill(FB_MULTI(f)->cur->fb);
   if (len)
-    return len;
+    {
+      fbmulti_get_ptrs(f);
+      return len;
+    }
 
   // Current buf returned EOF
-  // Update the information on end of this buffer
-  fbmulti_subbuf_get_end(FB_MULTI(f)->cur);
-
-  // Take the next one if exists
+  // Take the next one if exists and redo
   if (fbmulti_subbuf_next(f))
     return fbmulti_refill(f);
   else
     return 0;
 }
 
-static void
-fbmulti_get_len(struct fastbuf *f)
-{
-  ASSERT(f->seek);
-  FB_MULTI(f)->len = 0;
-  
-  CLIST_FOR_EACH(struct subbuf *, n, *(FB_MULTI(f)->subbufs))
-    {
-      n->begin = FB_MULTI(f)->len;
-      fbmulti_subbuf_get_end(n);
-      FB_MULTI(f)->len = n->end;
-    }
-}
-
 static int
 fbmulti_seek(struct fastbuf *f, ucw_off_t pos, int whence)
 {
+  fbmulti_set_ptrs(f);
   switch(whence)
     {
     case SEEK_SET:
-      if (f->pos > pos)
+      if (pos > FB_MULTI(f)->len)
+	bthrow(f, "seek", "Seek out of range");
+
+      while (pos > FB_MULTI(f)->cur->end) // Moving forward
 	{
-	  FB_MULTI(f)->cur = clist_head(FB_MULTI(f)->subbufs);
-	  FB_MULTI(f)->cur->begin = 0;
-	  f->pos = 0;
-	  return fbmulti_seek(f, pos, SEEK_SET);
+	  int r = fbmulti_subbuf_next(f);
+	  ASSERT(r);
 	}
 
-      do
+      while (pos < FB_MULTI(f)->cur->begin) // Moving backwards
 	{
-	  fbmulti_subbuf_get_end(FB_MULTI(f)->cur);
-	  if (pos < FB_MULTI(f)->cur->end)
-	    break;
-
-	  if (!fbmulti_subbuf_next(f))
-	    {
-	      if (pos == FB_MULTI(f)->cur->end)
-		break;
-	      else
-		bthrow(f, "seek", "Seek out of range");
-	    }
-
+	  int r = fbmulti_subbuf_prev(f);
+	  ASSERT(r);
 	}
-      while (1);
 
-      bsetpos(FB_MULTI(f)->cur->fb, (pos - FB_MULTI(f)->cur->begin));
-      f->pos = pos;
-      f->bptr = f->bstop = f->buffer;
+      // Now cur is the right buffer.
+      FB_MULTI(f)->cur->fb->seek(FB_MULTI(f)->cur->fb, (pos - FB_MULTI(f)->cur->begin), SEEK_SET);
+
+      fbmulti_get_ptrs(f);
       return 1;
-      break;
 
     case SEEK_END:
-      fbmulti_get_len(f);
-      return fbmulti_seek(f, FB_MULTI(f)->len+pos, SEEK_SET);
-      break;
+      return fbmulti_seek(f, FB_MULTI(f)->len + pos, SEEK_SET);
 
     default:
       ASSERT(0);
     }
 }
 
-static void
-fbmulti_update_capability(struct fastbuf *f)
-{
-  // FB Multi is only a proxy to other fastbufs ... if any of them lacks
-  // support of any feature, FB Multi also provides no support of that feature
-  f->refill = fbmulti_refill;
-  f->seek = fbmulti_seek;
-
-  CLIST_FOR_EACH(struct subbuf *, n, *(FB_MULTI(f)->subbufs))
-    {
-      ASSERT(n->fb->refill);
-
-      if (!n->fb->seek)
-	f->seek = NULL;
-    }
-}
-
 static void
 fbmulti_close(struct fastbuf *f)
 {
-  CLIST_FOR_EACH(struct subbuf *, n, *(FB_MULTI(f)->subbufs))
-    if (n->allow_close)
-      bclose(n->fb);
+  CLIST_FOR_EACH(struct subbuf *, n, FB_MULTI(f)->subbufs)
+    bclose(n->fb);
 
   mp_delete(FB_MULTI(f)->mp);
 }
 
 struct fastbuf *
-fbmulti_create(uns bufsize, ...)
+fbmulti_create(void)
 {
-  struct mempool *mp = mp_new(bufsize);
-  struct fastbuf *fb_out = mp_alloc(mp, sizeof(struct fb_multi));
-  FB_MULTI(fb_out)->mp = mp;
-
-  struct fastbuf *fb_in;
-  clist *subbufs = mp_alloc(mp, sizeof(clist));
-  clist_init(subbufs);
-  FB_MULTI(fb_out)->subbufs = subbufs;
-
-  va_list args;
-  va_start(args, bufsize);
-  while (fb_in = va_arg(args, struct fastbuf *))
-    fbmulti_append(fb_out, fb_in, 1);
-  
-  va_end(args);
-
-  FB_MULTI(fb_out)->cur = clist_head(subbufs);
-
-  fb_out->buffer = mp_alloc(mp, bufsize);
-  fb_out->bptr = fb_out->bstop = fb_out->buffer;
-  fb_out->bufend = fb_out->buffer + bufsize;
-  fb_out->name = FB_MULTI_NAME;
+  struct mempool *mp = mp_new(1024);
+  struct fastbuf *fb_out = mp_alloc_zero(mp, sizeof(struct fb_multi));
+  struct fb_multi *fbm = FB_MULTI(fb_out);
 
-  fbmulti_update_capability(fb_out);
+  fbm->mp = mp;
+  fbm->len = 0;
+
+  clist_init(&fbm->subbufs);
+
+  fb_out->name = FB_MULTI_NAME;
+  fb_out->refill = fbmulti_refill;
+  fb_out->seek = fbmulti_seek;
   fb_out->close = fbmulti_close;
 
   return fb_out;
 }
 
 void
-fbmulti_append(struct fastbuf *f, struct fastbuf *fb, int allow_close)
+fbmulti_append(struct fastbuf *f, struct fastbuf *fb)
 {
-  struct subbuf *sb = mp_alloc(FB_MULTI(f)->mp, sizeof(struct subbuf));
+  struct subbuf *last = clist_tail(&FB_MULTI(f)->subbufs);
+
+  struct subbuf *sb = mp_alloc(FB_MULTI(f)->mp, sizeof(*sb));
   sb->fb = fb;
-  sb->allow_close = allow_close;
-  clist_add_tail(FB_MULTI(f)->subbufs, &(sb->n));
-  fbmulti_update_capability(f);
+  clist_add_tail(&FB_MULTI(f)->subbufs, &(sb->n));
+
+  ASSERT(fb->refill);
+
+  if (fb->seek)
+    {
+      if (f->seek)
+	{
+	  sb->begin = last ? last->end : 0;
+	  bseek(fb, 0, SEEK_END);
+	  FB_MULTI(f)->len = sb->end = sb->begin + btell(fb);
+	}
+
+      bsetpos(fb, 0);
+    }
+
+  else
+    {
+      f->seek = NULL;
+      sb->offset = btell(fb);
+      sb->begin = 0;
+      sb->end = 0;
+    }
+
+  if (!last)
+    {
+      FB_MULTI(f)->cur = sb;
+      fbmulti_get_ptrs(f);
+    }
 }
 
 void
 fbmulti_remove(struct fastbuf *f, struct fastbuf *fb)
 {
+  bflush(f);
   if (fb)
     {
-      CLIST_FOR_EACH(struct subbuf *, n, *(FB_MULTI(f)->subbufs))
+      CLIST_FOR_EACH(struct subbuf *, n, FB_MULTI(f)->subbufs)
 	if (fb == n->fb)
 	  {
-	    // TODO: fix seek positions
 	    clist_remove(&(n->n));
-	    fbmulti_update_capability(f);
 	    return;
 	  }
 
-      die("Given fastbuf %p not in given fbmulti %p.", fb, f);
+      die("Given fastbuf %p not in given fbmulti %p", fb, f);
     }
   else
-    clist_init(FB_MULTI(f)->subbufs);
-
-  fbmulti_update_capability(f);
-}
-
-static void fbmulti_flatten_internal(struct fastbuf *f, clist *c, int allow_close)
-{
-  CLIST_FOR_EACH(struct subbuf *, n, *c)
-    {
-      if (strcmp(n->fb->name, FB_MULTI_NAME))
-	fbmulti_append(f, n->fb, n->allow_close && allow_close);
-      
-      else
-	{
-	  fbmulti_flatten_internal(f, FB_MULTI(n->fb)->subbufs, allow_close && n->allow_close);
-	  if (allow_close && n->allow_close)
-	    {
-	      FB_MULTI(n->fb)->subbufs = mp_alloc(FB_MULTI(n->fb)->mp, sizeof(clist));
-	      clist_init(FB_MULTI(n->fb)->subbufs);
-	      bclose(n->fb);
-	    }
-	}
-    }
-}
-
-void
-fbmulti_flatten(struct fastbuf *f)
-{
-  if (strcmp(f->name, FB_MULTI_NAME))
-    {
-      DBG("fbmulti: given fastbuf isn't fbmulti");
-      return;
-    }
-  
-  clist *c = FB_MULTI(f)->subbufs;
-  FB_MULTI(f)->subbufs = mp_alloc(FB_MULTI(f)->mp, sizeof(clist));
-  clist_init(FB_MULTI(f)->subbufs);
-
-  fbmulti_flatten_internal(f, c, 1);
-  FB_MULTI(f)->cur = clist_head(FB_MULTI(f)->subbufs);
-  f->bptr = f->bstop = f->buffer;
-  f->pos = 0;
+    clist_init(&FB_MULTI(f)->subbufs);
 }
 
 #ifdef TEST
@@ -280,7 +249,7 @@ int main(int argc, char **argv)
 {
   if (argc < 2)
     {
-      fprintf(stderr, "You must specify a test (r, w, o)\n");
+      fprintf(stderr, "You must specify a test (r, m, i, n)\n");
       return 1;
     }
   switch (*argv[1])
@@ -289,10 +258,13 @@ int main(int argc, char **argv)
         {
 	  char *data[] = { "One\nLine", "Two\nLines", "Th\nreeLi\nnes\n" };
 	  struct fastbuf fb[ARRAY_SIZE(data)];
-	  for (uns i=0;i<ARRAY_SIZE(data);i++)
+	  for (uint i=0;i<ARRAY_SIZE(data);i++)
 	    fbbuf_init_read(&fb[i], data[i], strlen(data[i]), 0);
 
-	  struct fastbuf *f = fbmulti_create(4, &fb[0], &fb[1], &fb[2], NULL);
+	  struct fastbuf *f = fbmulti_create();
+	  fbmulti_append(f, &fb[0]);
+	  fbmulti_append(f, &fb[1]);
+	  fbmulti_append(f, &fb[2]);
 
 	  char buffer[9];
 	  while (bgets(f, buffer, 9))
@@ -305,14 +277,16 @@ int main(int argc, char **argv)
 	{
 	  char *data[] = { "Mnl", "ige" };
 	  struct fastbuf fb[ARRAY_SIZE(data)];
-	  for (uns i=0;i<ARRAY_SIZE(data);i++)
+	  for (uint i=0;i<ARRAY_SIZE(data);i++)
 	    fbbuf_init_read(&fb[i], data[i], strlen(data[i]), 0);
 
-	  struct fastbuf *f = fbmulti_create(4, &fb[0], &fb[1], NULL);
+	  struct fastbuf *f = fbmulti_create();
+	  fbmulti_append(f, &fb[0]);
+	  fbmulti_append(f, &fb[1]);
 
 	  int pos[] = {0, 3, 1, 4, 2, 5};
 
-	  for (uns i=0;i<ARRAY_SIZE(pos);i++)
+	  for (uint i=0;i<ARRAY_SIZE(pos);i++)
 	    {
 	      bsetpos(f, pos[i]);
 	      putchar(bgetc(f));
@@ -330,7 +304,12 @@ int main(int argc, char **argv)
 	  fbbuf_init_read(&fb[2], data + 2, 2, 0);
 	  fbbuf_init_read(&fb[3], data + 4, 1, 0);
 
-	  struct fastbuf *f = fbmulti_create(8, &fb[0], &fb[1], &fb[2], &fb[1], &fb[3], NULL);
+	  struct fastbuf *f = fbmulti_create();
+	  fbmulti_append(f, &fb[0]);
+	  fbmulti_append(f, &fb[1]);
+	  fbmulti_append(f, &fb[2]);
+	  fbmulti_append(f, &fb[1]);
+	  fbmulti_append(f, &fb[3]);
 
 	  char buffer[9];
 	  while(bgets(f, buffer, 9))
@@ -339,12 +318,11 @@ int main(int argc, char **argv)
 	  bclose(f);
 	  break;
 	}
-      case 'f':
       case 'n':
 	{
 	  char *data[] = { "Nested", "Data", "As", "In", "Real", "Usage", };
 	  struct fastbuf fb[ARRAY_SIZE(data)];
-	  for (uns i=0;i<ARRAY_SIZE(data);i++)
+	  for (uint i=0;i<ARRAY_SIZE(data);i++)
 	    fbbuf_init_read(&fb[i], data[i], strlen(data[i]), 0);
 
 	  struct fastbuf sp;
@@ -353,29 +331,29 @@ int main(int argc, char **argv)
 	  struct fastbuf nl;
 	  fbbuf_init_read(&nl, "\n", 1, 0);
 
-	  struct fastbuf *f = fbmulti_create(4,
-	      fbmulti_create(5,
-		&fb[0],
-		&sp,
-		&fb[1],
-		NULL),
-	      &nl,
-	      fbmulti_create(7,
-		&fb[2],
-		&sp,
-		&fb[3],
-		NULL),
-	      &nl,
-	      fbmulti_create(3,
-		&fb[4],
-		&sp,
-		&fb[5],
-		NULL),
-	      &nl,
-	      NULL);
-
-	  if (*argv[1] == 'f')
-	    fbmulti_flatten(f);
+	  struct fastbuf *f = fbmulti_create();
+	  struct fastbuf *ff;
+
+	  ff = fbmulti_create();
+	  fbmulti_append(ff, &fb[0]);
+	  fbmulti_append(ff, &sp);
+	  fbmulti_append(ff, &fb[1]);
+	  fbmulti_append(f, ff);
+	  fbmulti_append(f, &nl);
+
+	  ff = fbmulti_create();
+	  fbmulti_append(ff, &fb[2]);
+	  fbmulti_append(ff, &sp);
+	  fbmulti_append(ff, &fb[3]);
+	  fbmulti_append(f, ff);
+	  fbmulti_append(f, &nl);
+
+	  ff = fbmulti_create();
+	  fbmulti_append(ff, &fb[4]);
+	  fbmulti_append(ff, &sp);
+	  fbmulti_append(ff, &fb[5]);
+	  fbmulti_append(f, ff);
+	  fbmulti_append(f, &nl);
 
 	  char buffer[20];
 	  while (bgets(f, buffer, 20))