Changeset dc87f3fd in mainline

Timestamp:

2011-03-28T20:19:16Z (14 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

df147c7

Parents:

fd89cf9

git-author:

Vojtech Horky <> (2011-03-28 20:19:16)

git-committer:

Jiri Svoboda <jiri@…> (2011-03-28 20:19:16)

Message:

Devman must be robust against short reads.

Location:

uspace/srv/devman

Files:

• devman.c (modified) (1 diff)
• util.c (modified) (1 diff)
• util.h (modified) (1 diff)

uspace/srv/devman/devman.c

@@ -266 +266 @@
         }
         
-        if (read(fd, buf, len) <= 0) {
+        ssize_t read_bytes = safe_read(fd, buf, len);
+        if (read_bytes <= 0) {
                 printf(NAME ": unable to read file '%s'.\n", conf_path);
                 goto cleanup;
         }
-        buf[len] = 0;
+        buf[read_bytes] = 0;
         
         suc = parse_match_ids(buf, ids);

uspace/srv/devman/util.c

@@ -111 +111 @@
 }
 
+ssize_t safe_read(int fd, void *buffer, size_t size)
+{
+        if (size == 0) {
+                return 0;
+        }
+
+        uint8_t *buf_ptr = (uint8_t *) buffer;
+
+        size_t total_read = 0;
+        while (total_read < size) {
+                ssize_t bytes_read = read(fd, buf_ptr, size - total_read);
+                if (bytes_read < 0) {
+                        /* Error. */
+                        return bytes_read;
+                } else if (bytes_read == 0) {
+                        /* Possibly end of file. */
+                        break;
+                } else {
+                        /* Read at least something. */
+                        buf_ptr += bytes_read;
+                        total_read += bytes_read;
+                }
+        }
+
+        return (ssize_t) total_read;
+}
+
 /** @}
  */

uspace/srv/devman/util.h

@@ -47 +47 @@
 extern void replace_char(char *, char, char);
 
+extern ssize_t safe_read(int, void *, size_t);
+
 #endif