--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/buffer.c	Tue Aug 26 18:40:01 2008 -0700
@@ -0,0 +1,268 @@
+/*=========================================================================*\
+* Input/Output interface for Lua programs
+* LuaSocket toolkit
+*
+* RCS ID: $Id: buffer.c,v 1.28 2007/06/11 23:44:54 diego Exp $
+\*=========================================================================*/
+#include "lua.h"
+#include "lauxlib.h"
+
+#include "buffer.h"
+
+/*=========================================================================*\
+* Internal function prototypes
+\*=========================================================================*/
+static int recvraw(p_buffer buf, size_t wanted, luaL_Buffer *b);
+static int recvline(p_buffer buf, luaL_Buffer *b);
+static int recvall(p_buffer buf, luaL_Buffer *b);
+static int buffer_get(p_buffer buf, const char **data, size_t *count);
+static void buffer_skip(p_buffer buf, size_t count);
+static int sendraw(p_buffer buf, const char *data, size_t count, size_t *sent);
+
+/* min and max macros */
+#ifndef MIN
+#define MIN(x, y) ((x) < (y) ? x : y)
+#endif
+#ifndef MAX
+#define MAX(x, y) ((x) > (y) ? x : y)
+#endif
+
+/*=========================================================================*\
+* Exported functions
+\*=========================================================================*/
+/*-------------------------------------------------------------------------*\
+* Initializes module
+\*-------------------------------------------------------------------------*/
+int buffer_open(lua_State *L) {
+    (void) L;
+    return 0;
+}
+
+/*-------------------------------------------------------------------------*\
+* Initializes C structure 
+\*-------------------------------------------------------------------------*/
+void buffer_init(p_buffer buf, p_io io, p_timeout tm) {
+	buf->first = buf->last = 0;
+    buf->io = io;
+    buf->tm = tm;
+    buf->received = buf->sent = 0;
+    buf->birthday = timeout_gettime();
+}
+
+/*-------------------------------------------------------------------------*\
+* object:getstats() interface
+\*-------------------------------------------------------------------------*/
+int buffer_meth_getstats(lua_State *L, p_buffer buf) {
+    lua_pushnumber(L, buf->received);
+    lua_pushnumber(L, buf->sent);
+    lua_pushnumber(L, timeout_gettime() - buf->birthday);
+    return 3;
+}
+
+/*-------------------------------------------------------------------------*\
+* object:setstats() interface
+\*-------------------------------------------------------------------------*/
+int buffer_meth_setstats(lua_State *L, p_buffer buf) {
+    buf->received = (long) luaL_optnumber(L, 2, buf->received); 
+    buf->sent = (long) luaL_optnumber(L, 3, buf->sent); 
+    if (lua_isnumber(L, 4)) buf->birthday = timeout_gettime() - lua_tonumber(L, 4);
+    lua_pushnumber(L, 1);
+    return 1;
+}
+
+/*-------------------------------------------------------------------------*\
+* object:send() interface
+\*-------------------------------------------------------------------------*/
+int buffer_meth_send(lua_State *L, p_buffer buf) {
+    int top = lua_gettop(L);
+    int err = IO_DONE;
+    size_t size = 0, sent = 0;
+    const char *data = luaL_checklstring(L, 2, &size);
+    long start = (long) luaL_optnumber(L, 3, 1);
+    long end = (long) luaL_optnumber(L, 4, -1);
+    p_timeout tm = timeout_markstart(buf->tm);
+    if (start < 0) start = (long) (size+start+1);
+    if (end < 0) end = (long) (size+end+1);
+    if (start < 1) start = (long) 1;
+    if (end > (long) size) end = (long) size;
+    if (start <= end) err = sendraw(buf, data+start-1, end-start+1, &sent);
+    /* check if there was an error */
+    if (err != IO_DONE) {
+        lua_pushnil(L);
+        lua_pushstring(L, buf->io->error(buf->io->ctx, err)); 
+        lua_pushnumber(L, sent+start-1);
+    } else {
+        lua_pushnumber(L, sent+start-1);
+        lua_pushnil(L);
+        lua_pushnil(L);
+    }
+#ifdef LUASOCKET_DEBUG
+    /* push time elapsed during operation as the last return value */
+    lua_pushnumber(L, timeout_gettime() - timeout_getstart(tm));
+#endif
+    return lua_gettop(L) - top;
+}
+
+/*-------------------------------------------------------------------------*\
+* object:receive() interface
+\*-------------------------------------------------------------------------*/
+int buffer_meth_receive(lua_State *L, p_buffer buf) {
+    int err = IO_DONE, top = lua_gettop(L);
+    luaL_Buffer b;
+    size_t size;
+    const char *part = luaL_optlstring(L, 3, "", &size);
+    p_timeout tm = timeout_markstart(buf->tm);
+    /* initialize buffer with optional extra prefix 
+     * (useful for concatenating previous partial results) */
+    luaL_buffinit(L, &b);
+    luaL_addlstring(&b, part, size);
+    /* receive new patterns */
+    if (!lua_isnumber(L, 2)) {
+        const char *p= luaL_optstring(L, 2, "*l");
+        if (p[0] == '*' && p[1] == 'l') err = recvline(buf, &b);
+        else if (p[0] == '*' && p[1] == 'a') err = recvall(buf, &b); 
+        else luaL_argcheck(L, 0, 2, "invalid receive pattern");
+        /* get a fixed number of bytes (minus what was already partially 
+         * received) */
+    } else err = recvraw(buf, (size_t) lua_tonumber(L, 2)-size, &b);
+    /* check if there was an error */
+    if (err != IO_DONE) {
+        /* we can't push anyting in the stack before pushing the
+         * contents of the buffer. this is the reason for the complication */
+        luaL_pushresult(&b);
+        lua_pushstring(L, buf->io->error(buf->io->ctx, err)); 
+        lua_pushvalue(L, -2); 
+        lua_pushnil(L);
+        lua_replace(L, -4);
+    } else {
+        luaL_pushresult(&b);
+        lua_pushnil(L);
+        lua_pushnil(L);
+    }
+#ifdef LUASOCKET_DEBUG
+    /* push time elapsed during operation as the last return value */
+    lua_pushnumber(L, timeout_gettime() - timeout_getstart(tm));
+#endif
+    return lua_gettop(L) - top;
+}
+
+/*-------------------------------------------------------------------------*\
+* Determines if there is any data in the read buffer
+\*-------------------------------------------------------------------------*/
+int buffer_isempty(p_buffer buf) {
+    return buf->first >= buf->last;
+}
+
+/*=========================================================================*\
+* Internal functions
+\*=========================================================================*/
+/*-------------------------------------------------------------------------*\
+* Sends a block of data (unbuffered)
+\*-------------------------------------------------------------------------*/
+#define STEPSIZE 8192
+static int sendraw(p_buffer buf, const char *data, size_t count, size_t *sent) {
+    p_io io = buf->io;
+    p_timeout tm = buf->tm;
+    size_t total = 0;
+    int err = IO_DONE;
+    while (total < count && err == IO_DONE) {
+        size_t done;
+        size_t step = (count-total <= STEPSIZE)? count-total: STEPSIZE;
+        err = io->send(io->ctx, data+total, step, &done, tm);
+        total += done;
+    }
+    *sent = total;
+    buf->sent += total;
+    return err;
+}
+
+/*-------------------------------------------------------------------------*\
+* Reads a fixed number of bytes (buffered)
+\*-------------------------------------------------------------------------*/
+static int recvraw(p_buffer buf, size_t wanted, luaL_Buffer *b) {
+    int err = IO_DONE;
+    size_t total = 0;
+    while (err == IO_DONE) {
+        size_t count; const char *data;
+        err = buffer_get(buf, &data, &count);
+        count = MIN(count, wanted - total);
+        luaL_addlstring(b, data, count);
+        buffer_skip(buf, count);
+        total += count;
+        if (total >= wanted) break;
+    }
+    return err;
+}
+
+/*-------------------------------------------------------------------------*\
+* Reads everything until the connection is closed (buffered)
+\*-------------------------------------------------------------------------*/
+static int recvall(p_buffer buf, luaL_Buffer *b) {
+    int err = IO_DONE;
+    size_t total = 0;
+    while (err == IO_DONE) {
+        const char *data; size_t count;
+        err = buffer_get(buf, &data, &count);
+        total += count;
+        luaL_addlstring(b, data, count);
+        buffer_skip(buf, count);
+    }
+    if (err == IO_CLOSED) {
+        if (total > 0) return IO_DONE;
+        else return IO_CLOSED;
+    } else return err;
+}
+
+/*-------------------------------------------------------------------------*\
+* Reads a line terminated by a CR LF pair or just by a LF. The CR and LF 
+* are not returned by the function and are discarded from the buffer
+\*-------------------------------------------------------------------------*/
+static int recvline(p_buffer buf, luaL_Buffer *b) {
+    int err = IO_DONE;
+    while (err == IO_DONE) {
+        size_t count, pos; const char *data;
+        err = buffer_get(buf, &data, &count);
+        pos = 0;
+        while (pos < count && data[pos] != '\n') {
+            /* we ignore all \r's */
+            if (data[pos] != '\r') luaL_putchar(b, data[pos]);
+            pos++;
+        }
+        if (pos < count) { /* found '\n' */
+            buffer_skip(buf, pos+1); /* skip '\n' too */
+            break; /* we are done */
+        } else /* reached the end of the buffer */
+            buffer_skip(buf, pos);
+    }
+    return err;
+}
+
+/*-------------------------------------------------------------------------*\
+* Skips a given number of bytes from read buffer. No data is read from the
+* transport layer
+\*-------------------------------------------------------------------------*/
+static void buffer_skip(p_buffer buf, size_t count) {
+    buf->received += count;
+    buf->first += count;
+    if (buffer_isempty(buf)) 
+        buf->first = buf->last = 0;
+}
+
+/*-------------------------------------------------------------------------*\
+* Return any data available in buffer, or get more data from transport layer
+* if buffer is empty
+\*-------------------------------------------------------------------------*/
+static int buffer_get(p_buffer buf, const char **data, size_t *count) {
+    int err = IO_DONE;
+    p_io io = buf->io;
+    p_timeout tm = buf->tm;
+    if (buffer_isempty(buf)) {
+        size_t got;
+        err = io->recv(io->ctx, buf->data, BUF_SIZE, &got, tm);
+        buf->first = 0;
+        buf->last = got;
+    }
+    *count = buf->last - buf->first;
+    *data = buf->data + buf->first;
+    return err;
+}