Handle screendumps for all framebuffer sizes

readx() treats a partial read as an error but also consumes the data,
Now exactly the amount of data needed for the screendump is requested.

This bug showed up for framebuffers that were not a multiple of 640
bytes.

Also fix a compiler warning related to handing pipe() failure.

Change-Id: I8b1713923e156d4e3424784152e5dc5cbc7d478d

1 files changed, 9 insertions, 7 deletions

diff --git a/adb/framebuffer_service.c b/adb/framebuffer_service.c
index 20c08d23f..fa7fd98dc 100644
--- a/adb/framebuffer_service.c
+++ b/adb/framebuffer_service.c
@@ -55,13 +55,13 @@ struct fbinfo {
 void framebuffer_service(int fd, void *cookie)
 {
     struct fbinfo fbinfo;
-    unsigned int i;
+    unsigned int i, bsize;
     char buf[640];
     int fd_screencap;
     int w, h, f;
     int fds[2];
 
-    if (pipe(fds) < 0) goto done;
+    if (pipe(fds) < 0) goto pipefail;
 
     pid_t pid = fork();
     if (pid < 0) goto done;
@@ -164,17 +164,19 @@ void framebuffer_service(int fd, void *cookie)
     if(writex(fd, &fbinfo, sizeof(fbinfo))) goto done;
 
     /* write data */
-    for(i = 0; i < fbinfo.size; i += sizeof(buf)) {
-      if(readx(fd_screencap, buf, sizeof(buf))) goto done;
-      if(writex(fd, buf, sizeof(buf))) goto done;
+    for(i = 0; i < fbinfo.size; i += bsize) {
+      bsize = sizeof(buf);
+      if (i + bsize > fbinfo.size)
+        bsize = fbinfo.size - i;
+      if(readx(fd_screencap, buf, bsize)) goto done;
+      if(writex(fd, buf, bsize)) goto done;
     }
-    if(readx(fd_screencap, buf, fbinfo.size % sizeof(buf))) goto done;
-    if(writex(fd, buf, fbinfo.size % sizeof(buf))) goto done;
 
 done:
     TEMP_FAILURE_RETRY(waitpid(pid, NULL, 0));
 
     close(fds[0]);
     close(fds[1]);
+pipefail:
     close(fd);
 }