[t:3314] Merge fix for #3314 to main (readlink doesn't append a NUL). Refs #3314.

{{{
svn merge -c28759 https://svn.tokutek.com/tokudb/toku/tokudb.3312
}}}
.


git-svn-id: file:///svn/toku/tokudb@28761 c7de825b-a66e-492c-adef-691d508d4ae1

linux/file.c

@@ -74,14 +74,16 @@ try_again_after_handling_write_error(int fd, size_t len, ssize_t r_write) {
                 ctime_r(&t, tstr);
 
                 const int MY_MAX_PATH = 256;
-                char fname[MY_MAX_PATH], symname[MY_MAX_PATH];
+                char fname[MY_MAX_PATH], symname[MY_MAX_PATH+1];
                 sprintf(fname, "/proc/%d/fd/%d", getpid(), fd);
                 ssize_t n = readlink(fname, symname, MY_MAX_PATH);
 
                 if ((int)n == -1)
                     fprintf(stderr, "%.24s Tokudb No space when writing %"PRIu64" bytes to fd=%d ", tstr, (uint64_t) len, fd);
-                else
-                    fprintf(stderr, "%.24s Tokudb No space when writing %"PRIu64" bytes to %*s ", tstr, (uint64_t) len, (int) n, symname); 
+                else {
+		    tstr[n] = 0; // readlink doesn't append a NUL to the end of the buffer.
+                    fprintf(stderr, "%.24s Tokudb No space when writing %"PRIu64" bytes to %*s ", tstr, (uint64_t) len, (int) n, symname);
+		}
                 fprintf(stderr, "retry in %d second%s\n", toku_write_enospc_sleep, toku_write_enospc_sleep > 1 ? "s" : "");
                 fflush(stderr);
             }

windows/file.c

@@ -252,13 +252,15 @@ try_again_after_handling_write_error(int fd, size_t len, ssize_t r_write) {
                 //  Is this important?
                 //
                 const int MY_MAX_PATH = 256;
-                char fname[MY_MAX_PATH], symname[MY_MAX_PATH];
+                char fname[MY_MAX_PATH], symname[MY_MAX_PATH+1];
                 sprintf(fname, "/proc/%d/fd/%d", getpid(), fd);
                 ssize_t n = readlink(fname, symname, MY_MAX_PATH);
                 if ((int)n == -1)
                     fprintf(stderr, "%.24s Tokudb No space when writing %"PRIu64" bytes to fd=%d ", tstr, (uint64_t) len, fd);
-                else
-                    fprintf(stderr, "%.24s Tokudb No space when writing %"PRIu64" bytes to %*s ", tstr, (uint64_t) len, (int) n, symname); 
+                else {
+		    tstr[n] = 0; // readlink doesn't append a NUL to the end of the buffer.
+                    fprintf(stderr, "%.24s Tokudb No space when writing %"PRIu64" bytes to %*s ", tstr, (uint64_t) len, (int) n, symname);
+		}
 #else
                 fprintf(stderr, "%.24s Tokudb No space when writing %"PRIu64" bytes to fd=%d ", tstr, (uint64_t) len, fd);
 #endif