From f5be42dd4a3346059819fdba379e7abac9549625 Mon Sep 17 00:00:00 2001
From: Martin Mares <mj@ucw.cz>
Date: Sat, 22 Nov 2003 18:21:22 +0000
Subject: [PATCH] Added very simple functions for emulating a fastbuf stream
 over a static buffer. The struct fastbuf is allocated statically as well to
 make everything as simple and as fast as possible.

---
 lib/Makefile    |  2 +-
 lib/fastbuf.h   | 10 ++++++++++
 lib/fb-buffer.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 62 insertions(+), 1 deletion(-)
 create mode 100644 lib/fb-buffer.c

diff --git a/lib/Makefile b/lib/Makefile
index d31c66be..7bb2c7c4 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -9,7 +9,7 @@ LIBSH_MODS=alloc alloc_str ctmatch db fastbuf fb-file fb-mem lists \
 	wordsplit str_ctype str_upper bucket conf object sorter \
 	finger proctitle ipaccess profile bitsig randomkey \
 	hashfunc base64 base224 fb-temp fb-mmap fb-printf urlkey \
-	partmap fb-limfd
+	partmap fb-limfd fb-buffer
 LIBSH_MOD_PATHS=$(addprefix obj/lib/,$(LIBSH_MODS)) $(CUSTOM_LIB_MODULES)
 
 obj/lib/libsh.a: $(addsuffix .o,$(LIBSH_MOD_PATHS))
diff --git a/lib/fastbuf.h b/lib/fastbuf.h
index 8699fe40..266ea220 100644
--- a/lib/fastbuf.h
+++ b/lib/fastbuf.h
@@ -86,6 +86,16 @@ struct fastbuf *bopen_mm(byte *name, uns mode);
 
 struct fastbuf *bopen_limited_fd(int fd, uns bufsize, uns limit);
 
+/* FastIO on static buffers */
+
+void fbbuf_init_read(struct fastbuf *f, byte *buffer, uns size);
+void fbbuf_init_write(struct fastbuf *f, byte *buffer, uns size);
+static inline uns
+fbbuf_count_written(struct fastbuf *f)
+{
+  return f->bptr - f->bstop;
+}
+
 /* Configuring stream parameters */
 
 int bconfig(struct fastbuf *f, uns type, int data);
diff --git a/lib/fb-buffer.c b/lib/fb-buffer.c
new file mode 100644
index 00000000..03c8e321
--- /dev/null
+++ b/lib/fb-buffer.c
@@ -0,0 +1,51 @@
+/*
+ *	Sherlock Library -- Fast Buffered I/O on Static Buffers
+ *
+ *	(c) 2003 Martin Mares <mj@ucw.cz>
+ *
+ *	This software may be freely distributed and used according to the terms
+ *	of the GNU Lesser General Public License.
+ */
+
+#include "lib/lib.h"
+#include "lib/fastbuf.h"
+
+static int
+fbbuf_refill(struct fastbuf *f UNUSED)
+{
+  return 0;
+}
+
+void
+fbbuf_init_read(struct fastbuf *f, byte *buf, uns size)
+{
+  f->buffer = f->bptr = buf;
+  f->bstop = f->bufend = buf + size;
+  f->name = "fbbuf-read";
+  f->pos = size;
+  f->refill = fbbuf_refill;
+  f->spout = NULL;
+  f->seek = NULL;
+  f->close = NULL;
+  f->config = NULL;
+}
+
+static void
+fbbuf_spout(struct fastbuf *f UNUSED)
+{
+  die("fbbuf: buffer overflow on write");
+}
+
+void
+fbbuf_init_write(struct fastbuf *f, byte *buf, uns size)
+{
+  f->buffer = f->bstop = f->bptr = buf;
+  f->bufend = buf + size;
+  f->name = "fbbuf-write";
+  f->pos = size;
+  f->refill = NULL;
+  f->spout = fbbuf_spout;
+  f->seek = NULL;
+  f->close = NULL;
+  f->config = NULL;
+}
-- 
2.39.5