X-Git-Url: http://git.demorecorder.com/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fxcb_out.c;h=cecf7cb19398251d221d9b6b7fdad181be255fba;hb=7f0bc778c88ab2f565cc05d5d3d5ee4c8d1388a1;hp=04b8365fd561a6c3be319138fbe9a8ba2ac13474;hpb=662479760c42fc38c458381ee3eaed92e2c8b733;p=free-sw%2Fxcb%2Flibxcb

diff --git a/src/xcb_out.c b/src/xcb_out.c
index 04b8365..cecf7cb 100644
--- a/src/xcb_out.c
+++ b/src/xcb_out.c
@@ -27,9 +27,20 @@
 
 #include <assert.h>
 #include <stdlib.h>
+#include <unistd.h>
 #include <string.h>
 #include <errno.h>
 
+#ifndef __GNUC__
+# if HAVE_ALLOCA_H
+#  include <alloca.h>
+# else
+#  ifdef _AIX
+ #pragma alloca
+#  endif
+# endif
+#endif
+
 #include "xcb.h"
 #include "xcbext.h"
 #include "xcbint.h"
@@ -47,6 +58,40 @@ static int force_sequence_wrap(XCBConnection *c)
     return ret;
 }
 
+static int _xcb_write(const int fd, char (*buf)[], int *count)
+{
+    int n = write(fd, *buf, *count);
+    if(n > 0)
+    {
+        *count -= n;
+        if(*count)
+            memmove(*buf, *buf + n, *count);
+    }
+    return n;
+}
+
+static int _xcb_writev(const int fd, struct iovec *vec, int count)
+{
+    int n = writev(fd, vec, count);
+    if(n > 0)
+    {
+        int rem = n;
+        for(; count; --count, ++vec)
+        {
+            int cur = vec->iov_len;
+            if(cur > rem)
+                cur = rem;
+            vec->iov_len -= cur;
+            vec->iov_base = (char *) vec->iov_base + cur;
+            rem -= cur;
+            if(vec->iov_len)
+                break;
+        }
+        assert(rem == 0);
+    }
+    return n;
+}
+
 /* Public interface */
 
 CARD32 XCBGetMaximumRequestLength(XCBConnection *c)
@@ -70,9 +115,11 @@ CARD32 XCBGetMaximumRequestLength(XCBConnection *c)
 
 int XCBSendRequest(XCBConnection *c, unsigned int *request, struct iovec *vector, const XCBProtocolRequest *req)
 {
+    static const char pad[3];
     int ret;
     int i;
-    struct iovec prefix[2];
+    struct iovec *padded;
+    int padlen = 0;
     CARD16 shortlen = 0;
     CARD32 longlen = 0;
     enum workarounds workaround = WORKAROUND_NONE;
@@ -82,6 +129,24 @@ int XCBSendRequest(XCBConnection *c, unsigned int *request, struct iovec *vector
     assert(vector != 0);
     assert(req->count > 0);
 
+    /* set the major opcode, and the minor opcode for extensions */
+    if(req->ext)
+    {
+        const XCBQueryExtensionRep *extension = XCBGetExtensionData(c, req->ext);
+        /* TODO: better error handling here, please! */
+        assert(extension && extension->present);
+        ((CARD8 *) vector[0].iov_base)[0] = extension->major_opcode;
+        ((CARD8 *) vector[0].iov_base)[1] = req->opcode;
+
+        /* do we need to work around the X server bug described in glx.xml? */
+        if(strcmp(req->ext->name, "GLX") &&
+                ((req->opcode == 17 && ((CARD32 *) vector[0].iov_base)[0] == 0x10004) ||
+                 req->opcode == 21))
+            workaround = WORKAROUND_GLX_GET_FB_CONFIGS_BUG;
+    }
+    else
+        ((CARD8 *) vector[0].iov_base)[0] = req->opcode;
+
     /* put together the length field, possibly using BIGREQUESTS */
     for(i = 0; i < req->count; ++i)
         longlen += XCB_CEIL(vector[i].iov_len) >> 2;
@@ -98,45 +163,47 @@ int XCBSendRequest(XCBConnection *c, unsigned int *request, struct iovec *vector
         longlen = 0;
     }
 
+    padded =
+#ifdef HAVE_ALLOCA
+        alloca
+#else
+        malloc
+#endif
+        ((req->count * 2 + 3) * sizeof(struct iovec));
     /* set the length field. */
-    i = 0;
-    prefix[i].iov_base = vector[0].iov_base;
-    prefix[i].iov_len = sizeof(CARD32);
-    vector[0].iov_base = ((char *) vector[0].iov_base) + sizeof(CARD32);
-    vector[0].iov_len -= sizeof(CARD32);
-    ((CARD16 *) prefix[i].iov_base)[1] = shortlen;
-    ++i;
+    ((CARD16 *) vector[0].iov_base)[1] = shortlen;
     if(!shortlen)
     {
+        padded[0].iov_base = vector[0].iov_base;
+        padded[0].iov_len = sizeof(CARD32);
+        vector[0].iov_base = ((char *) vector[0].iov_base) + sizeof(CARD32);
+        vector[0].iov_len -= sizeof(CARD32);
         ++longlen;
-        prefix[i].iov_base = &longlen;
-        prefix[i].iov_len = sizeof(CARD32);
-        ++i;
+        padded[1].iov_base = &longlen;
+        padded[1].iov_len = sizeof(CARD32);
+        padlen = 2;
     }
 
-    /* set the major opcode, and the minor opcode for extensions */
-    if(req->ext)
+    for(i = 0; i < req->count; ++i)
     {
-        const XCBQueryExtensionRep *extension = XCBGetExtensionData(c, req->ext);
-        /* TODO: better error handling here, please! */
-        assert(extension && extension->present);
-        ((CARD8 *) prefix[0].iov_base)[0] = extension->major_opcode;
-        ((CARD8 *) prefix[0].iov_base)[1] = req->opcode;
-
-        /* do we need to work around the X server bug described in glx.xml? */
-        if(strcmp(req->ext->name, "GLX") &&
-                ((req->opcode == 17 && ((CARD32 *) vector[0].iov_base)[0] == 0x10004) ||
-                 req->opcode == 21))
-            workaround = WORKAROUND_GLX_GET_FB_CONFIGS_BUG;
+        if(!vector[i].iov_len)
+            continue;
+        padded[padlen].iov_base = vector[i].iov_base;
+        padded[padlen++].iov_len = vector[i].iov_len;
+        if(!XCB_PAD(vector[i].iov_len))
+            continue;
+        padded[padlen].iov_base = (caddr_t) pad;
+        padded[padlen++].iov_len = XCB_PAD(vector[i].iov_len);
     }
-    else
-        ((CARD8 *) prefix[0].iov_base)[0] = req->opcode;
 
     /* get a sequence number and arrange for delivery. */
     pthread_mutex_lock(&c->iolock);
     if(req->isvoid && !force_sequence_wrap(c))
     {
         pthread_mutex_unlock(&c->iolock);
+#ifndef HAVE_ALLOCA
+        free(padded);
+#endif
         return -1;
     }
 
@@ -145,10 +212,11 @@ int XCBSendRequest(XCBConnection *c, unsigned int *request, struct iovec *vector
     if(!req->isvoid)
         _xcb_in_expect_reply(c, *request, workaround);
 
-    ret = _xcb_out_write_block(c, prefix, i);
-    if(ret > 0)
-        ret = _xcb_out_write_block(c, vector, req->count);
+    ret = _xcb_out_write_block(c, padded, padlen);
     pthread_mutex_unlock(&c->iolock);
+#ifndef HAVE_ALLOCA
+    free(padded);
+#endif
 
     return ret;
 }
@@ -199,8 +267,9 @@ int _xcb_out_write(XCBConnection *c)
     else
         n = _xcb_write(c->fd, &c->out.queue, &c->out.queue_len);
 
-    if(n < 0 && errno == EAGAIN)
-        n = 1;
+    /* XXX: should "nothing was written" be considered failure or
+     * success for this function? it's not an I/O error, but... */
+    n = (n > 0) || (n < 0 && errno == EAGAIN);
 
     if(c->out.vec_len)
     {
@@ -208,6 +277,7 @@ int _xcb_out_write(XCBConnection *c)
         for(i = 0; i < c->out.vec_len; ++i)
             if(c->out.vec[i].iov_len)
                 return n;
+        c->out.vec = 0;
         c->out.vec_len = 0;
     }
     return n;
@@ -215,63 +285,33 @@ int _xcb_out_write(XCBConnection *c)
 
 int _xcb_out_write_block(XCBConnection *c, struct iovec *vector, size_t count)
 {
-    static const char pad[3];
-    int i;
-    int len = 0;
-
-    for(i = 0; i < count; ++i)
-        len += XCB_CEIL(vector[i].iov_len);
-
-    /* Is the queue about to overflow? */
-    if(c->out.queue_len + len < sizeof(c->out.queue))
+    while(count && c->out.queue_len + vector[0].iov_len < sizeof(c->out.queue))
     {
-        /* No, this will fit. */
-        for(i = 0; i < count; ++i)
-        {
-            memcpy(c->out.queue + c->out.queue_len, vector[i].iov_base, vector[i].iov_len);
-            if(vector[i].iov_len & 3)
-                memset(c->out.queue + c->out.queue_len + vector[i].iov_len, 0, XCB_PAD(vector[i].iov_len));
-            c->out.queue_len += XCB_CEIL(vector[i].iov_len);
-        }
-        return len;
+        memcpy(c->out.queue + c->out.queue_len, vector[0].iov_base, vector[0].iov_len);
+        c->out.queue_len += vector[0].iov_len;
+        ++vector, --count;
     }
+    if(!count)
+        return 1;
+
+    memmove(vector + 1, vector, count++ * sizeof(struct iovec));
+    vector[0].iov_base = c->out.queue;
+    vector[0].iov_len = c->out.queue_len;
+    c->out.queue_len = 0;
 
     assert(!c->out.vec_len);
     assert(!c->out.vec);
-    c->out.vec = malloc(sizeof(struct iovec) * (1 + count * 2));
-    if(!c->out.vec)
-        return -1;
-    if(c->out.queue_len)
-    {
-        c->out.vec[c->out.vec_len].iov_base = c->out.queue;
-        c->out.vec[c->out.vec_len++].iov_len = c->out.queue_len;
-        c->out.queue_len = 0;
-    }
-    for(i = 0; i < count; ++i)
-    {
-        if(!vector[i].iov_len)
-            continue;
-        c->out.vec[c->out.vec_len].iov_base = vector[i].iov_base;
-        c->out.vec[c->out.vec_len++].iov_len = vector[i].iov_len;
-        if(!XCB_PAD(vector[i].iov_len))
-            continue;
-        c->out.vec[c->out.vec_len].iov_base = (void *) pad;
-        c->out.vec[c->out.vec_len++].iov_len = XCB_PAD(vector[i].iov_len);
-    }
-    if(_xcb_out_flush(c) <= 0)
-        len = -1;
-    free(c->out.vec);
-    c->out.vec = 0;
-
-    return len;
+    c->out.vec_len = count;
+    c->out.vec = vector;
+    return _xcb_out_flush(c);
 }
 
 int _xcb_out_flush(XCBConnection *c)
 {
     int ret = 1;
-    c->out.request_written = c->out.request;
     while(ret && (c->out.queue_len || c->out.vec_len))
         ret = _xcb_conn_wait(c, /*should_write*/ 1, &c->out.cond);
+    c->out.request_written = c->out.request;
     pthread_cond_broadcast(&c->out.cond);
     return ret;
 }