generator: Use quoted string literals in many places

This change was done almost entirely automatically using the script
below.  This uses the OCaml lexer to read the source files and extract
the strings and locations.  Strings which are "candidates" (in this
case, longer than 3 lines) are replaced in the output with quoted
string literals.

Since the OCaml lexer is used, it already substitutes all escape
sequences correctly.  I diffed the output of the generator and it is
identical after this change, except for UUIDs, which change because of
how Utils.stable_uuid is implemented.

Thanks: Nicolas Ojeda Bar

$ ocamlfind opt -package unix,compiler-libs.common find_strings.ml \
                -o find_strings.opt -linkpkg
$ for f in $( git ls-files -- \*.ml ) ; do ./find_strings.opt $f ; done

open Printf

let read_whole_file path =
  let buf = Buffer.create 16384 in
  let chan = open_in path in
  let maxlen = 16384 in
  let b = Bytes.create maxlen in
  let rec loop () =
    let r = input chan b 0 maxlen in
    if r > 0 then (
      Buffer.add_substring buf (Bytes.to_string b) 0 r;
      loop ()
    )
  in
  loop ();
  close_in chan;
  Buffer.contents buf

let count_chars c str =
  let count = ref 0 in
  for i = 0 to String.length str - 1 do
    if c = String.unsafe_get str i then incr count
  done;
  !count

let subs = ref []

let consider_string str loc =
  let nr_lines = count_chars '\n' str in
  if nr_lines > 3 then
    subs := (str, loc) :: !subs

let () =
  Lexer.init ();
  let filename = Sys.argv.(1) in
  let content = read_whole_file filename in
  let lexbuf = Lexing.from_string content in
  let rec loop () =
    let token = Lexer.token lexbuf in
    (match token with
     | Parser.EOF -> ();
     | STRING (s, loc, sopt) ->
        consider_string s loc; (* sopt? *)
        loop ();
     | token ->
        loop ();
    )
  in
  loop ();

  (* The list of subs is already reversed, which is convenient
   * because we must the file substitutions in reverse order.
   *)
  let subs = !subs in
  let new_content = ref content in
  List.iter (
    fun (str, loc) ->
      let { Location.loc_start = { pos_cnum = p1 };
            loc_end = { pos_cnum = p2 } } = loc in
      let len = String.length !new_content in
      let before = String.sub !new_content 0 (p1-1) in
      let after = String.sub !new_content (p2+1) (len - p2 - 1) in
      new_content := before ^ "{|" ^ str ^ "|}" ^ after
  ) subs;

  let new_content = !new_content in

  if content <> new_content then (
    (* Update the file in place. *)
    let new_filename = filename ^ ".new"
    and backup_filename = filename ^ ".bak" in
    let chan = open_out new_filename in
    fprintf chan "%s" new_content;
    close_out chan;
    Unix.rename filename backup_filename;
    Unix.rename new_filename filename
  )

generator/lua.ml

@@ -36,8 +36,7 @@ let generate_header = generate_header ~inputs:["generator/lua.ml"]
 let generate_lua_c () =
   generate_header CStyle LGPLv2plus;
 
-  pr "\
-#include <config.h>
+  pr {|#include <config.h>
 
 /* It is safe to call deprecated functions from this file. */
 #define GUESTFS_NO_WARN_DEPRECATED
@@ -67,12 +66,12 @@ let generate_lua_c () =
 #endif
 #endif
 
-#include \"ignore-value.h\"
+#include "ignore-value.h"
 
 #include <guestfs.h>
-#include \"guestfs-utils.h\"
+#include "guestfs-utils.h"
 
-#define GUESTFS_LUA_HANDLE \"guestfs handle\"
+#define GUESTFS_LUA_HANDLE "guestfs handle"
 
 /* This struct is managed on the Lua heap.  If the GC collects it,
  * the Lua '__gc' function is called which ends up calling
@@ -114,7 +113,7 @@ static uint64_t get_event (lua_State *L, int index);
 static uint64_t get_event_bitmask (lua_State *L, int index);
 static void push_event (lua_State *L, uint64_t event);
 
-";
+|};
 
   List.iter (
     function
@@ -125,20 +124,19 @@ static void push_event (lua_State *L, uint64_t event);
       pr "static void push_%s_list (lua_State *L, struct guestfs_%s_list *v);\n" typ typ
   ) (rstructs_used_by (actions |> external_functions));
 
-  pr "\
-
+  pr {|
 /* On the stack at 'index' should be a table.  Check if 'name' (string)
  * is a key in this table, and if so execute 'code'.  While 'code' is
  * executing, the top of stack (ie. index == -1) is the value of 'name'.
  */
-#define OPTARG_IF_SET(index, name, code) \\
-  do {                                   \\
-    lua_pushliteral (L, name);           \\
-    lua_gettable (L, index);             \\
-    if (!lua_isnil (L, -1)) {            \\
-      code                               \\
-    }                                    \\
-    lua_pop (L, 1);                      \\
+#define OPTARG_IF_SET(index, name, code) \
+  do {                                   \
+    lua_pushliteral (L, name);           \
+    lua_gettable (L, index);             \
+    if (!lua_isnil (L, -1)) {            \
+      code                               \
+    }                                    \
+    lua_pop (L, 1);                      \
   } while (0)
 
 /* Create a new connection. */
@@ -151,21 +149,21 @@ guestfs_int_lua_create (lua_State *L)
   char err[256];
 
   if (lua_gettop (L) == 1) {
-    OPTARG_IF_SET (1, \"environment\",
+    OPTARG_IF_SET (1, "environment",
         if (! lua_toboolean (L, -1))
             flags |= GUESTFS_CREATE_NO_ENVIRONMENT;
     );
-    OPTARG_IF_SET (1, \"close_on_exit\",
+    OPTARG_IF_SET (1, "close_on_exit",
         if (! lua_toboolean (L, -1))
             flags |= GUESTFS_CREATE_NO_CLOSE_ON_EXIT;
     );
   }
   else if (lua_gettop (L) > 1)
-    return luaL_error (L, \"Guestfs.create: too many arguments\");
+    return luaL_error (L, "Guestfs.create: too many arguments");
 
   g = guestfs_create_flags (flags);
   if (!g)
-    return luaL_error (L, \"Guestfs.create: cannot create handle: %%s\",
+    return luaL_error (L, "Guestfs.create: cannot create handle: %%s",
                        guestfs_int_strerror (errno, err, sizeof err));
 
   guestfs_set_error_handler (g, NULL, NULL);
@@ -235,15 +233,15 @@ error__tostring (lua_State *L)
   const char *msg;
   char err[256];
 
-  lua_pushliteral (L, \"code\");
+  lua_pushliteral (L, "code");
   lua_gettable (L, 1);
   code = luaL_checkint (L, -1);
-  lua_pushliteral (L, \"msg\");
+  lua_pushliteral (L, "msg");
   lua_gettable (L, 1);
   msg = luaL_checkstring (L, -1);
 
   if (code)
-    lua_pushfstring (L, \"%%s: %%s\", msg,
+    lua_pushfstring (L, "%%s: %%s", msg,
                      guestfs_int_strerror (code, err, sizeof err));
   else
     lua_pushstring (L, msg);
@@ -259,15 +257,15 @@ last_error (lua_State *L, guestfs_h *g)
    * and 'code' fields.
    */
   lua_newtable (L);
-  lua_pushliteral (L, \"msg\");
+  lua_pushliteral (L, "msg");
   lua_pushstring (L, guestfs_last_error (g));
   lua_settable (L, -3);
-  lua_pushliteral (L, \"code\");
+  lua_pushliteral (L, "code");
   lua_pushinteger (L, guestfs_last_errno (g));
   lua_settable (L, -3);
 
   lua_newtable (L);
-  lua_pushliteral (L, \"__tostring\");
+  lua_pushliteral (L, "__tostring");
   lua_pushcfunction (L, error__tostring);
   lua_settable (L, -3);
 
@@ -299,7 +297,7 @@ get_per_handle_table (lua_State *L, guestfs_h *g)
   }
 }
 
-/* Free the per-handle Lua table.  It doesn't literally \"free\"
+/* Free the per-handle Lua table.  It doesn't literally "free"
  * anything since the GC will do that.  It just removes the entry
  * from the global registry.
  */
@@ -324,8 +322,8 @@ guestfs_int_lua_set_event_callback (lua_State *L)
   struct event_state *es;
 
   if (g == NULL)
-    return luaL_error (L, \"Guestfs.%%s: handle is closed\",
-                       \"set_event_callback\");
+    return luaL_error (L, "Guestfs.%%s: handle is closed",
+                       "set_event_callback");
 
   event_bitmask = get_event_bitmask (L, 3);
 
@@ -340,7 +338,7 @@ guestfs_int_lua_set_event_callback (lua_State *L)
 
   es = malloc (sizeof *es);
   if (!es)
-    return luaL_error (L, \"failed to allocate event_state\");
+    return luaL_error (L, "failed to allocate event_state");
   es->next = u->es;
   es->L = L;
   es->u = u;
@@ -375,7 +373,7 @@ event_callback_wrapper (guestfs_h *g,
   lua_rawgeti (L, -1, es->ref);
 
   if (!lua_isfunction (L, -1)) {
-    fprintf (stderr, \"lua-guestfs: %%s: internal error: no closure found for g = %%p, eh = %%d\\n\",
+    fprintf (stderr, "lua-guestfs: %%s: internal error: no closure found for g = %%p, eh = %%d\n",
              __func__, g, eh);
     goto out;
   }
@@ -395,21 +393,21 @@ event_callback_wrapper (guestfs_h *g,
   case 0: /* call ok - do nothing */
     break;
   case LUA_ERRRUN:
-    fprintf (stderr, \"lua-guestfs: %%s: unexpected error in event handler: \",
+    fprintf (stderr, "lua-guestfs: %%s: unexpected error in event handler: ",
              __func__);
     print_any (L, -1, stderr);
     lua_pop (L, 1);
-    fprintf (stderr, \"\\n\");
+    fprintf (stderr, "\n");
     break;
   case LUA_ERRERR: /* can probably never happen */
-    fprintf (stderr, \"lua-guestfs: %%s: error calling error handler\\n\",
+    fprintf (stderr, "lua-guestfs: %%s: error calling error handler\n",
              __func__);
     break;
   case LUA_ERRMEM:
-    fprintf (stderr, \"lua-guestfs: %%s: memory allocation failed\\n\", __func__);
+    fprintf (stderr, "lua-guestfs: %%s: memory allocation failed\n", __func__);
     break;
   default:
-    fprintf (stderr, \"lua-guestfs: %%s: unknown error\\n\", __func__);
+    fprintf (stderr, "lua-guestfs: %%s: unknown error\n", __func__);
   }
 
   /* Pop the per-handle table. */
@@ -426,8 +424,8 @@ guestfs_int_lua_delete_event_callback (lua_State *L)
   int eh;
 
   if (g == NULL)
-    return luaL_error (L, \"Guestfs.%%s: handle is closed\",
-                       \"delete_event_callback\");
+    return luaL_error (L, "Guestfs.%%s: handle is closed",
+                       "delete_event_callback");
 
   eh = luaL_checkint (L, 2);
 
@@ -436,7 +434,7 @@ guestfs_int_lua_delete_event_callback (lua_State *L)
   return 0;
 }
 
-";
+|};
 
   (* Actions. *)
   List.iter (
@@ -632,8 +630,7 @@ guestfs_int_lua_delete_event_callback (lua_State *L)
       pr "\n"
   ) (actions |> external_functions |> sort);
 
-  pr "\
-static struct userdata *
+  pr {|static struct userdata *
 get_handle (lua_State *L, int index)
 {
   struct userdata *u;
@@ -653,7 +650,7 @@ get_string_list (lua_State *L, int index)
 
   strs = malloc ((len+1) * sizeof (char *));
   if (strs == NULL) {
-    luaL_error (L, \"get_string_list: malloc failed: %%s\",
+    luaL_error (L, "get_string_list: malloc failed: %%s",
                 guestfs_int_strerror (errno, err, sizeof err));
     /*NOTREACHED*/
     return NULL;
@@ -707,15 +704,15 @@ get_int64 (lua_State *L, int index)
   switch (lua_type (L, index)) {
   case LUA_TSTRING:
     s = luaL_checkstring (L, index);
-    if (sscanf (s, \"%%\" SCNi64, &r) != 1)
-      return luaL_error (L, \"int64 parameter expected\");
+    if (sscanf (s, "%%" SCNi64, &r) != 1)
+      return luaL_error (L, "int64 parameter expected");
     return r;
 
   case LUA_TNUMBER:
     return luaL_checkint (L, index);
 
   default:
-    return luaL_error (L, \"expecting 64 bit integer\");
+    return luaL_error (L, "expecting 64 bit integer");
   }
 }
 
@@ -724,7 +721,7 @@ push_int64 (lua_State *L, int64_t i64)
 {
   char s[64];
 
-  snprintf (s, sizeof s, \"%%\" PRIi64, i64);
+  snprintf (s, sizeof s, "%%" PRIi64, i64);
   lua_pushstring (L, s);
 }
 
@@ -746,14 +743,14 @@ push_int64_array (lua_State *L, const int64_t *array, size_t len)
 static void
 print_any (lua_State *L, int index, FILE *out)
 {
-  lua_getglobal(L, \"tostring\");
+  lua_getglobal(L, "tostring");
   lua_pushvalue (L, index >= 0 ? index : index-1);
   lua_call (L, 1, 1);
-  fprintf (out, \"%%s\", luaL_checkstring (L, -1));
+  fprintf (out, "%%s", luaL_checkstring (L, -1));
   lua_pop (L, 1);
 }
 
-";
+|};
 
   (* Code to handle events. *)
   pr "\
@@ -764,7 +761,7 @@ static const char *event_all[] = {
     fun (event, _) -> pr "  \"%s\",\n" event
   ) events;
 
-  pr "  NULL
+  pr {|  NULL
 };
 
 static uint64_t
@@ -797,7 +794,7 @@ get_event (lua_State *L, int index)
 static void
 push_event (lua_State *L, uint64_t event)
 {
-";
+|};
 
   List.iter (
     fun (event, i) ->
@@ -869,35 +866,33 @@ push_event (lua_State *L, uint64_t event)
       generate_push_struct_list typ
   ) (rstructs_used_by (actions |> external_functions));
 
-  pr "\
-/* Metamethods.
+  pr {|/* Metamethods.
  * See: http://article.gmane.org/gmane.comp.lang.lua.general/95065
  */
 static luaL_Reg metamethods[] = {
-  { \"__gc\", guestfs_int_lua_finalizer },
+  { "__gc", guestfs_int_lua_finalizer },
   { NULL, NULL }
 };
 
 /* Module functions. */
 static luaL_Reg functions[] = {
-  { \"create\", guestfs_int_lua_create },
+  { "create", guestfs_int_lua_create },
   { NULL, NULL }
 };
 
 /* Methods. */
 static luaL_Reg methods[] = {
-  { \"close\", guestfs_int_lua_close },
-  { \"set_event_callback\", guestfs_int_lua_set_event_callback },
-  { \"delete_event_callback\", guestfs_int_lua_delete_event_callback },
+  { "close", guestfs_int_lua_close },
+  { "set_event_callback", guestfs_int_lua_set_event_callback },
+  { "delete_event_callback", guestfs_int_lua_delete_event_callback },
 
-";
+|};
 
   List.iter (
     fun { name } -> pr "  { \"%s\", guestfs_int_lua_%s },\n" name name
   ) (actions |> external_functions |> sort);
 
-  pr "\
-
+  pr {|
   { NULL, NULL }
 };
 
@@ -910,7 +905,7 @@ make_version_string (char *version, size_t size)
   g = guestfs_create ();
   v = guestfs_version (g);
   snprintf (version, size,
-            \"libguestfs %%\" PRIi64 \".%%\" PRIi64 \".%%\" PRIi64 \"%%s\",
+            "libguestfs %%" PRIi64 ".%%" PRIi64 ".%%" PRIi64 "%%s",
             v->major, v->minor, v->release, v->extra);
   free (v);
   guestfs_close (g);
@@ -940,7 +935,7 @@ luaopen_guestfs (lua_State *L)
 #endif
 
   /* Set __index field of metatable to point to methods table. */
-  lua_setfield (L, -2, \"__index\");
+  lua_setfield (L, -2, "__index");
 
   /* Pop metatable, it is no longer needed. */
   lua_pop (L, 1);
@@ -954,28 +949,28 @@ luaopen_guestfs (lua_State *L)
 #endif
 
   /* Globals in the module namespace. */
-  lua_pushliteral (L, \"event_all\");
+  lua_pushliteral (L, "event_all");
   push_string_list (L, (char **) event_all);
   lua_settable (L, -3);
 
   /* Add _COPYRIGHT, etc. fields to the module namespace. */
-  lua_pushliteral (L, \"_COPYRIGHT\");
-  lua_pushliteral (L, \"Copyright (C) %s Red Hat Inc.\");
+  lua_pushliteral (L, "_COPYRIGHT");
+  lua_pushliteral (L, "Copyright (C) %s Red Hat Inc.");
   lua_settable (L, -3);
 
-  lua_pushliteral (L, \"_DESCRIPTION\");
-  lua_pushliteral (L, \"Lua binding to libguestfs\");
+  lua_pushliteral (L, "_DESCRIPTION");
+  lua_pushliteral (L, "Lua binding to libguestfs");
   lua_settable (L, -3);
 
-  lua_pushliteral (L, \"_VERSION\");
+  lua_pushliteral (L, "_VERSION");
   make_version_string (v, sizeof v);
   lua_pushlstring (L, v, strlen (v));
   lua_settable (L, -3);
 
   /* Return module table, so users choose their own name for the module:
-   * local G = require \"guestfs\"
+   * local G = require "guestfs"
    * g = G.create ()
    */
   return 1;
 }
-" copyright_years;
+|} copyright_years;