[PATCH] Make file-based lookup more interruptable

[Doug Evans <dje@google.com>]

Hi.

This patch makes, for example, "b 'foo.c':bar" more interruptable.

I put the QUIT calls at two logical levels for robustness and clarity:
iterate_over_symtabs and map_symtabs_matching_filename.
I plan to do the same for other QUIT calls I've already added
and plan to add.

2015-05-15  Doug Evans  <dje@google.com>

	* completer.c (location_completer): Protect file_to_match with cleanup.
	* dwarf2read.c (dw2_map_symtabs_matching_filename): Add QUIT calls.
	* psymtab.c (psym_map_symtabs_matching_filename): Add QUIT call.
	* symtab.c (iterate_over_symtabs): Add QUIT calls.

diff --git a/gdb/completer.c b/gdb/completer.c
index c8c0e4c..c796951 100644
--- a/gdb/completer.c
+++ b/gdb/completer.c
@@ -195,7 +195,6 @@ location_completer (struct cmd_list_element *ignore,
    int quoted = *text == '\'' || *text == '"';
    int quote_char = '\0';
    const char *colon = NULL;
-  char *file_to_match = NULL;
    const char *symbol_start = text;
    const char *orig_text = text;
    size_t text_len;
@@ -241,12 +240,17 @@ location_completer (struct cmd_list_element *ignore,
      text++;
    text_len = strlen (text);

-  /* Where is the file name?  */
-  if (colon)
+  /* Where is the file name?
+     If the text includes a colon, they want completion only on a
+     symbol name after the colon.  Otherwise, we need to complete on
+     symbols as well as on files.  */
+  if (colon != NULL)
      {
-      char *s;
+      char *s, *file_to_match;
+      struct cleanup *cleanup;

-      file_to_match = (char *) xmalloc (colon - text + 1);
+      file_to_match = xmalloc (colon - text + 1);
+      cleanup = make_cleanup (xfree, file_to_match);
        strncpy (file_to_match, text, colon - text + 1);
        /* Remove trailing colons and quotes from the file name.  */
        for (s = file_to_match + (colon - text);
@@ -254,15 +258,9 @@ location_completer (struct cmd_list_element *ignore,
  	   s--)
  	if (*s == ':' || *s == quote_char)
  	  *s = '\0';
-    }
-  /* If the text includes a colon, they want completion only on a
-     symbol name after the colon.  Otherwise, we need to complete on
-     symbols as well as on files.  */
-  if (colon)
-    {
        list = make_file_symbol_completion_list (symbol_start, word,
  					       file_to_match);
-      xfree (file_to_match);
+      do_cleanups (cleanup);
      }
    else
      {
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 4d892d8..ca8573a 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -3448,6 +3448,8 @@ dw2_map_symtabs_matching_filename (struct objfile  
*objfile, const char *name,
        struct dwarf2_per_cu_data *per_cu = dw2_get_cu (i);
        struct quick_file_names *file_data;

+      QUIT;
+
        /* We only need to look at symtabs not already expanded.  */
        if (per_cu->v.quick->compunit_symtab)
  	continue;
@@ -3461,6 +3463,8 @@ dw2_map_symtabs_matching_filename (struct objfile  
*objfile, const char *name,
  	  const char *this_name = file_data->file_names[j];
  	  const char *this_real_name;

+	  QUIT;
+
  	  if (compare_filenames_for_search (this_name, name))
  	    {
  	      if (dw2_map_expand_apply (objfile, per_cu, name, real_path,
diff --git a/gdb/psymtab.c b/gdb/psymtab.c
index 383e4c4..27ba2ba 100644
--- a/gdb/psymtab.c
+++ b/gdb/psymtab.c
@@ -169,6 +169,8 @@ psym_map_symtabs_matching_filename (struct objfile  
*objfile,

    ALL_OBJFILE_PSYMTABS_REQUIRED (objfile, pst)
    {
+    QUIT;
+
      /* We can skip shared psymtabs here, because any file name will be
         attached to the unshared psymtab.  */
      if (pst->user != NULL)
diff --git a/gdb/symtab.c b/gdb/symtab.c
index 72df872..f06622a 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -443,6 +443,8 @@ iterate_over_symtabs (const char *name,

    ALL_OBJFILES (objfile)
    {
+    QUIT;
+
      if (iterate_over_some_symtabs (name, real_path, callback, data,
  				   objfile->compunit_symtabs, NULL))
        {
@@ -456,6 +458,8 @@ iterate_over_symtabs (const char *name,

    ALL_OBJFILES (objfile)
    {
+    QUIT;
+
      if (objfile->sf
  	&& objfile->sf->qf->map_symtabs_matching_filename (objfile,
  							   name,