Daemon: fix handling of errors from xread and xwrite.

[libguestfs.git] / daemon / daemon.h

diff --git a/daemon/daemon.h b/daemon/daemon.h
index 166f3bf..86c6876 100644 (file)
--- a/daemon/daemon.h
+++ b/daemon/daemon.h
@@ -36,11 +36,13 @@ extern int sysroot_len;
 
 extern char *sysroot_path (const char *path);
 
-extern int xwrite (int sock, const void *buf, size_t len);
-extern int xread (int sock, void *buf, size_t len);
+extern int xwrite (int sock, const void *buf, size_t len)
+  __attribute__((__warn_unused_result__));
+extern int xread (int sock, void *buf, size_t len)
+  __attribute__((__warn_unused_result__));
 
 extern int add_string (char ***argv, int *size, int *alloc, const char *str);
-extern int count_strings (char * const* const argv);
+extern int count_strings (char *const *argv);
 extern void sort_strings (char **argv, int len);
 extern void free_strings (char **argv);
 extern void free_stringslen (char **argv, int len);
@@ -48,9 +50,9 @@ extern void free_stringslen (char **argv, int len);
 extern int command (char **stdoutput, char **stderror, const char *name, ...);
 extern int commandr (char **stdoutput, char **stderror, const char *name, ...);
 extern int commandv (char **stdoutput, char **stderror,
-                     char * const* const argv);
+                     char *const *argv);
 extern int commandrv (char **stdoutput, char **stderror,
-                      char * const* const argv);
+                      char const* const *argv);
 
 extern char **split_lines (char *str);
 
@@ -91,7 +93,7 @@ extern guestfs_int_lvm_vg_list *parse_command_line_vgs (void);
 extern guestfs_int_lvm_lv_list *parse_command_line_lvs (void);
 
 /*-- in proto.c --*/
-extern void main_loop (int sock);
+extern void main_loop (int sock) __attribute__((noreturn));
 
 /* ordinary daemon functions use these to indicate errors */
 extern void reply_with_error (const char *fs, ...)
@@ -116,7 +118,7 @@ extern void cancel_receive (void);
  * Note max write size if GUESTFS_MAX_CHUNK_SIZE.
  */
 extern int send_file_write (const void *buf, int len);
-extern void send_file_end (int cancel);
+extern int send_file_end (int cancel);
 
 /* only call this if there is a FileOut parameter */
 extern void reply (xdrproc_t xdrp, char *ret);
@@ -124,11 +126,11 @@ extern void reply (xdrproc_t xdrp, char *ret);
 /* Helper for functions that need a root filesystem mounted.
  * NB. Cannot be used for FileIn functions.
  */
-#define NEED_ROOT(errcode)                                             \
+#define NEED_ROOT(fail_stmt)                                           \
   do {                                                                 \
     if (!root_mounted) {                                               \
       reply_with_error ("%s: you must call 'mount' first to mount the root filesystem", __func__); \
-      return (errcode);                                                        \
+      fail_stmt;                                                       \
     }                                                                  \
   }                                                                    \
   while (0)
@@ -136,11 +138,11 @@ extern void reply (xdrproc_t xdrp, char *ret);
 /* Helper for functions that need an argument ("path") that is absolute.
  * NB. Cannot be used for FileIn functions.
  */
-#define ABS_PATH(path,errcode)                                         \
+#define ABS_PATH(path,fail_stmt)                                       \
   do {                                                                 \
     if ((path)[0] != '/') {                                            \
       reply_with_error ("%s: path must start with a / character", __func__); \
-      return (errcode);                                                        \
+      fail_stmt;                                                       \
     }                                                                  \
   } while (0)
 
@@ -171,13 +173,13 @@ extern void reply (xdrproc_t xdrp, char *ret);
  * because we intend in future to make device parameters a distinct
  * type from filenames.
  */
-#define NEED_ROOT_OR_IS_DEVICE(path,errcode) \
+#define REQUIRE_ROOT_OR_RESOLVE_DEVICE(path,fail_stmt)                 \
   do {                                                                 \
     if (strncmp ((path), "/dev/", 5) == 0)                             \
-      IS_DEVICE ((path),(errcode));                                    \
+      RESOLVE_DEVICE ((path), fail_stmt);                              \
     else {                                                             \
-      NEED_ROOT ((errcode));                                           \
-      ABS_PATH ((path),(errcode));                                     \
+      NEED_ROOT (fail_stmt);                                           \
+      ABS_PATH ((path),fail_stmt);                                     \
     }                                                                  \
   } while (0)