Re: -file-list-exec-source-files

Bob Rossi
2004-03-29T20:55:53Z

What do you think?

On Thu, Mar 11, 2004 at 08:25:08AM -0500, Bob Rossi wrote:
> What do you think?
>
> Bob Rossi
>
> On Sat, Mar 06, 2004 at 10:57:00AM -0500, Bob Rossi wrote:
> > Elena, thanks for taking the time to review my patch.
> >
> > When is a good point to resubmit a patch? After every review, or after
> > all the issues are ironed out?
> >
> > > > Here is an initial patch for -file-list-exec-source-files.
> > > > Some feedback would be appreciated.
> > > >
> > > > I ran the testsuite and the results are the same before and after this
> > > > patch.
> > > >
> > > > Index: gdb/ChangeLog
> > > > * dbxread.c (read_dbx_symtab): set pst->dirname when known
> > >
> > > Each entry should start with capital letter and end with period.
> > >
> > > I see some coding standards are not adhered to throughout the code.
> > > Most noticeably "foo ( int a )" should be "foo (int a)". Similarly for
> > > calls.
> >
> > Ok, I will try to fix all of the coding standard errors. Is there a
> > program I can run on the source files before I create the diff that
> > formats the code according to the standard?
> >
> > >
> > > >
> > > > Index: gdb/dbxread.c
> > > > ===================================================================
> > > > Index: gdb/dwarf2read.c
> > > > ===================================================================
> > >
> > > These are ok
> >
> > Great!
> >
> > > >
> > > > Index: gdb/defs.h
> > > > ===================================================================
> > > > RCS file: /cvs/src/src/gdb/defs.h,v
> > > > retrieving revision 1.143
> > > > diff -w -u -r1.143 defs.h
> > > > --- gdb/defs.h 23 Feb 2004 19:26:14 -0000 1.143
> > > > +++ gdb/defs.h 25 Feb 2004 03:51:35 -0000
> > > > @@ -616,8 +616,6 @@
> > > >
> > > > extern void init_last_source_visited (void);
> > > >
> > > > -extern char *symtab_to_filename (struct symtab *);
> > > > -
> > > > /* From exec.c */
> > > >
> > > > extern void exec_set_section_offsets (bfd_signed_vma text_off,
> > > > Index: gdb/dwarf2read.c
> > > > ===================================================================
> > > > RCS file: /cvs/src/src/gdb/dwarf2read.c,v
> > > > retrieving revision 1.135
> > > > diff -w -u -r1.135 dwarf2read.c
> > > > --- gdb/dwarf2read.c 21 Feb 2004 02:13:35 -0000 1.135
> > > > +++ gdb/dwarf2read.c 25 Feb 2004 03:51:43 -0000
> > > > @@ -316,6 +316,7 @@
> > > > unsigned int offset;
> > > > unsigned int abbrev;
> > > > char *name;
> > > > + char *dirname;
> > > > int has_pc_info;
> > > > CORE_ADDR lowpc;
> > > > CORE_ADDR highpc;
> > > > @@ -1254,6 +1255,8 @@
> > > > objfile->global_psymbols.next,
> > > > objfile->static_psymbols.next);
> > > >
> > > > + pst->dirname = xstrdup ( comp_unit_die.dirname );
> > > > +
> > > > pst->read_symtab_private = (char *)
> > > > obstack_alloc (&objfile->objfile_obstack, sizeof (struct dwarf2_pinfo));
> > > > DWARF_INFO_BUFFER (pst) = dwarf_info_buffer;
> > > > @@ -4326,6 +4329,10 @@
> > > > /* Prefer DW_AT_MIPS_linkage_name over DW_AT_name. */
> > > > if (part_die->name == NULL)
> > > > part_die->name = DW_STRING (&attr);
> > > > + break;
> > > > + case DW_AT_comp_dir:
> > > > + if (part_die->dirname == NULL)
> > > > + part_die->dirname = DW_STRING (&attr);
> > >
> > > The dwarf2 specs say that the name is in the form ":pathname" or
> > > "hostname:pathname". Should we worry about the hostname? Does gcc emit
> > > that? I have looked at a few executables and didn't see the hostname
> > > part.
> >
> > It would probably just be best if you told me what case's you want me to
> > implement here. It seems that Jason Molenda understodd most of the
> > cases. I really don't know anything about what GCC emits and would would
> > be practical to implement.
> >
> > > > Index: gdb/source.c
> > > > ===================================================================
> > >
> > > this part I am not clear about.
> >
> > Ok, Ok. I thought about this a lot. I think I made the best decision and
> > can describe why.
> >
> > A few assumptions are in order. In order to get the fullname (abs path)
> > to a file, GDB need's three things. The directory the file was compiled
> > in (dirname), the filename in question (filename) and a list of paths
> > to search.
> >
> > > There is already a function called source_full_path_of() would it help
> > > if you used it?
> >
> > The function source_full_path_of does not take into account 'dirname'.
> > It calls openp, which is not capable of finding the fullname of a file,
> > since it doesn't understand what dirname is. Basically, I don't even
> > think this function (source_full_path_of) is "truly" capable of
> > finding the fullpath to a file. However, instead of removing it,
> > I left it, since caller's of this function might be using for something
> > I know nothing about.
> >
> > > What is the difference between find_and_open_source and
> > > open_source_file? I.e. why did you need to introduce it. I think it's
> > > not clear just from your comments about the file possibly baing moved
> > > around.
> >
> > open_source_file was left around for backwards compatibility. The unit
> > source.c was used to calling a function, with just passing the symtab,
> > and getting back the symtab with a valid fullname. I could remove all
> > occurences of this function and replace it with symtab_to_fullname.
> >
> > > I am a bit worried about the substitution of symtab_to_filename with
> > > symtab_to_fullname. The former returns null only if there is no
> > > symtab. The latter returns null when there is no symtab OR when it
> > > cannot find the file. So the behavior is slightly different.
> >
> > I basically think that the call -file-list-exec-source-files shouldn't
> > 'cache' it's results. GDB looks for each file, every time it is
> > requested to get the fullname. This is because, the user could have
> > changed the path, or moved/deleted the file. I don't think GDB should
> > just return the filename instead, of the fullname.
> >
> > So, if find_and_open_source couldn't "find and open the source file", it
> > returns NULL. Also, as a side effect, fullname in the [ps]ymtab also
> > get's set to NULL.
> >
> > The testsuite didn't seem to have a problem with this, and I think it
> > makes sense to not trick the caller into having results when it couldn't
> > find any.
> >
> > If the caller really wanted this functionality,
> > return s->filename; /* File not found. Just use short name */
> > I believe it should be the caller's responsibility.
> >
> > if ( symtab_to_fullname ( s ) == NULL )
> > /* use symtab->filename */
> > else
> > /* use symtab->fullname */
> >
> > It doesn't really make sense to return the filename and not state that
> > it is not really the fullname. Also, if the caller tries to access
> > s->fullname, it will not be successful, because the file simply isn't
> > there.
> >
> > > > RCS file: /cvs/src/src/gdb/source.c,v
> > > > retrieving revision 1.49
> > > > diff -w -u -r1.49 source.c
> > > > --- gdb/source.c 27 Jan 2004 23:19:51 -0000 1.49
> > > > +++ gdb/source.c 25 Feb 2004 03:51:45 -0000
> > > > @@ -805,30 +805,47 @@
> > > > return 1;
> > > > }
> > > >
> > > > -
> > > > -/* Open a source file given a symtab S. Returns a file descriptor or
> > > > - negative number for error. */
> > > > -
> > > > +/* This function is capable of finding the absolute path to a
> > > > + source file, and opening it, provided you give it an
> > > > + OBJFILE and FILENAME. Both the DIRNAME and FULLNAME are only
> > > > + added suggestions on where to find the file.
> > > > +
> > > > + OBJFILE should be the objfile associated with a psymtab or symtab.
> > > > + FILENAME should be the filename to open.
> > > > + DIRNAME is the compilation directory of a particular source file.
> > > > + Only some debug formats provide this info.
> > > > + FULLNAME can be the last known absolute path to the file in question.
> > > > +
> > > > + On Success
> > > > + A valid file descriptor is returned. ( the return value is positive )
> > > > + FULLNAME is set to the absolute path to the file just opened.
> > > > +
> > > > + On Failure
> > > > + A non valid file descriptor is returned. ( the return value is negitive )
> > > > + FULLNAME is set to NULL. */
> > > > int
> > > > -open_source_file (struct symtab *s)
> > > > +find_and_open_source (
> > > > + struct objfile *objfile,
> > > > + const char *filename,
> > > > + const char *dirname,
> > > > + char **fullname )
> > > > {
> > >
> > > coding standards....
> >
> > Ok.
> >
> > > > char *path = source_path;
> > > > const char *p;
> > > > int result;
> > > > - char *fullname;
> > > >
> > > > /* Quick way out if we already know its full name */
> > > > - if (s->fullname)
> > > > + if (*fullname)
> > > > {
> > > > - result = open (s->fullname, OPEN_MODE);
> > > > + result = open (*fullname, OPEN_MODE);
> > > > if (result >= 0)
> > > > return result;
> > > > /* Didn't work -- free old one, try again. */
> > > > - xmfree (s->objfile->md, s->fullname);
> > > > - s->fullname = NULL;
> > > > + xmfree (objfile->md, *fullname);
> > > > + *fullname = NULL;
> > > > }
> > > >
> > > > - if (s->dirname != NULL)
> > > > + if (dirname != NULL)
> > > > {
> > > > /* Replace a path entry of $cdir with the compilation directory name */
> > > > #define cdir_len 5
> > > > @@ -841,60 +858,102 @@
> > > > int len;
> > > >
> > > > path = (char *)
> > > > - alloca (strlen (source_path) + 1 + strlen (s->dirname) + 1);
> > > > + alloca (strlen (source_path) + 1 + strlen (dirname) + 1);
> > > > len = p - source_path;
> > > > strncpy (path, source_path, len); /* Before $cdir */
> > > > - strcpy (path + len, s->dirname); /* new stuff */
> > > > + strcpy (path + len, dirname); /* new stuff */
> > > > strcat (path + len, source_path + len + cdir_len); /* After $cdir */
> > > > }
> > > > }
> > > >
> > > > - result = openp (path, 0, s->filename, OPEN_MODE, 0, &s->fullname);
> > > > + result = openp (path, 0, filename, OPEN_MODE, 0, fullname);
> > > > if (result < 0)
> > > > {
> > > > /* Didn't work. Try using just the basename. */
> > > > - p = lbasename (s->filename);
> > > > - if (p != s->filename)
> > > > - result = openp (path, 0, p, OPEN_MODE, 0, &s->fullname);
> > > > + p = lbasename (filename);
> > > > + if (p != filename)
> > > > + result = openp (path, 0, p, OPEN_MODE, 0, fullname);
> > > > }
> > > >
> > > > if (result >= 0)
> > > > {
> > > > - fullname = s->fullname;
> > > > - s->fullname = mstrsave (s->objfile->md, s->fullname);
> > > > - xfree (fullname);
> > > > + char *tmp_fullname;
> > > > + tmp_fullname = *fullname;
> > > > + *fullname = mstrsave (objfile->md, *fullname);
> > > > + xfree (tmp_fullname);
> > > > }
> > > > return result;
> > > > }
> > > >
> > > > -/* Return the path to the source file associated with symtab. Returns NULL
> > > > - if no symtab. */
> > > > +/* Open a source file given a symtab S. Returns a file descriptor or
> > > > + negative number for error.
> > > > +
> > > > + This function is a convience function to find_and_open_source. */
> > > > +
> > > > +int
> > > > +open_source_file (struct symtab *s)
> > > > +{
> > > > + if (!s)
> > > > + return -1;
> > > > +
> > > > + return find_and_open_source ( s->objfile, s->filename, s->dirname, &s->fullname );
> > > > +}
> > > > +
> > > > +/* Finds the fullname that a symtab represents.
> > > > +
> > > > + If this functions finds the fullname, it will save it in ps->fullname
> > > > + and it will also return the value.
> > > >
> > > > + If this function fails to find the file that this symtab represents,
> > > > + NULL will be returned and ps->fullname will be set to NULL. */
> > > > char *
> > > > -symtab_to_filename (struct symtab *s)
> > > > +symtab_to_fullname (struct symtab *s)
> > > > {
> > > > - int fd;
> > > > + int r;
> > > >
> > > > if (!s)
> > > > return NULL;
> > > >
> > > > - /* If we've seen the file before, just return fullname. */
> > > > + /* Don't check s->fullname here, the file could have been
> > > > + deleted/moved/..., look for it again */
> > > > + r = find_and_open_source ( s->objfile, s->filename, s->dirname, &s->fullname);
> > > >
> > > > - if (s->fullname)
> > > > + if (r)
> > > > + {
> > > > + close (r);
> > > > return s->fullname;
> > > > + }
> > > >
> > > > - /* Try opening the file to setup fullname */
> > > > + return NULL;
> > > > +}
> > > >
> > > > - fd = open_source_file (s);
> > > > - if (fd < 0)
> > > > - return s->filename; /* File not found. Just use short name */
> > > > +/* Finds the fullname that a partial_symtab represents.
> > > >
> > > > - /* Found the file. Cleanup and return the full name */
> > > > + If this functions finds the fullname, it will save it in ps->fullname
> > > > + and it will also return the value.
> > > >
> > > > - close (fd);
> > > > - return s->fullname;
> > > > + If this function fails to find the file that this partial_symtab represents,
> > > > + NULL will be returned and ps->fullname will be set to NULL. */
> > > > +char *
> > > > +psymtab_to_fullname (struct partial_symtab *ps)
> > > > +{
> > > > + int r;
> > > > +
> > > > + if (!ps)
> > > > + return NULL;
> > > > +
> > > > + /* Don't check ps->fullname here, the file could have been
> > > > + deleted/moved/..., look for it again */
> > > > + r = find_and_open_source ( ps->objfile, ps->filename, ps->dirname, &ps->fullname);
> > > > +
> > > > + if (r)
> > > > + {
> > > > + close (r);
> > > > + return ps->fullname;
> > > > }
> > > > \f
> > > > + return NULL;
> > > > +}
> > > >
> > > > /* Create and initialize the table S->line_charpos that records
> > > > the positions of the lines in the source file, which is assumed
> > >
> > >
> > >
> > > > Index: gdb/source.h
> > > > ===================================================================
> > > > Index: gdb/symtab.c
> > > > ===================================================================
> > >
> > > These are obvious if the rest goes in.
> > >
> > >
> > > > Index: gdb/symtab.h
> > > > ===================================================================
> > >
> > > OK.
> > >
> > >
> > > > Index: gdb/mi/mi-cmd-file.c
> > > > ===================================================================
> > >
> > >
> > > > +static const char * const FILENAME = "filename";
> > > > +static const char * const FULLNAME = "fullname";
> > >
> > > I don't think these are necessary.
> >
> > It just unifies the output convention I am using in the
> > mi-cmd-file unit. What would you prefer to see?
> >
> > > >
> > > > /* Return to the client the absolute path and line number of the
> > > > current file being executed. */
> > > > @@ -39,7 +43,6 @@
> > > > if ( !mi_valid_noargs("mi_cmd_file_list_exec_source_file", argc, argv) )
> > > > error ("mi_cmd_file_list_exec_source_file: Usage: No args");
> > > >
> > > > -
> > > > /* Set the default file and line, also get them */
> > > > set_default_source_symtab_and_line();
> > > > st = get_current_source_symtab_and_line();
> > > > @@ -51,17 +54,67 @@
> > > > error ("mi_cmd_file_list_exec_source_file: No symtab");
> > > >
> > > > /* Extract the fullname if it is not known yet */
> > > > - if (st.symtab->fullname == NULL)
> > > > - symtab_to_filename (st.symtab);
> > > > -
> > > > - /* We may not be able to open the file (not available). */
> > > > - if (st.symtab->fullname == NULL)
> > > > - error ("mi_cmd_file_list_exec_source_file: File not found");
> > >
> > > Why get rid of the error message?
> >
> > Ok.
> >
> > > > + symtab_to_fullname (st.symtab);
> > > >
> > > > /* Print to the user the line, filename and fullname */
> > > > ui_out_field_int (uiout, "line", st.line);
> > > > - ui_out_field_string (uiout, "file", st.symtab->filename);
> > > > - ui_out_field_string (uiout, "fullname", st.symtab->fullname);
> > > > + ui_out_field_string (uiout, FILENAME, st.symtab->filename);
> > > > +
> > > > + /* We may not be able to open the file (not available). */
> > > > + if (st.symtab->fullname)
> > > > + ui_out_field_string (uiout, FULLNAME, st.symtab->fullname);
> > > > +
> > >
> > > if this test fails shouldn't some warning/error be issued?
> >
> > I don't know. I am thinking that GDB should just return the absolute
> > path to all of the source files it can find. If it can not find some,
> > should it issue a warning? That way the front end could say, "you need
> > to add a directory to the source search path".
> >
> > > > + return MI_CMD_DONE;
> > > > +}
> > > > +
> > > > +enum mi_cmd_result
> > > > +mi_cmd_file_list_exec_source_files(char *command, char **argv, int argc)
> > > > +{
> > > > + struct symtab *s;
> > > > + struct partial_symtab *ps;
> > > > + struct objfile *objfile;
> > > > +
> > > > + if ( !mi_valid_noargs("mi_cmd_file_list_exec_source_files", argc, argv) )
> > > > + error ("mi_cmd_file_list_exec_source_files: Usage: No args");
> > > > +
> > > > + /* Print the table header */
> > > > + ui_out_begin ( uiout, ui_out_type_list, "files");
> > > > +
> > > > + /* Look at all of the symtabs */
> > > > + ALL_SYMTABS (objfile, s)
> > > > + {
> > > > + ui_out_begin ( uiout, ui_out_type_tuple, NULL);
> > > > +
> > > > + ui_out_field_string (uiout, FILENAME, s->filename);
> > > > +
> > > > + /* Extract the fullname if it is not known yet */
> > > > + symtab_to_fullname (s);
> > > > +
> > > > + if (s->fullname)
> > > > + ui_out_field_string (uiout, FULLNAME, s->fullname);
> > > > +
> > > > + ui_out_end ( uiout, ui_out_type_tuple );
> > > > + }
> > > > +
> > > > + /* Look at all of the psymtabs */
> > > > + ALL_PSYMTABS (objfile, ps)
> > > > + {
> > > > + if (!ps->readin) {
> > >
> > > coding standards....
> >
> > Ok.
> >
> > > > + ui_out_begin ( uiout, ui_out_type_tuple, NULL);
> > > > +
> > > > + ui_out_field_string (uiout, FILENAME, ps->filename);
> > > > +
> > > > + /* Extract the fullname if it is not known yet */
> > > > + psymtab_to_fullname (ps);
> > > > +
> > > > + if (ps->fullname)
> > > > + ui_out_field_string (uiout, FULLNAME, ps->fullname);
> > > > +
> > > > + ui_out_end ( uiout, ui_out_type_tuple );
> > > > + }
> > > > + }
> > > > +
> > > > + ui_out_end ( uiout, ui_out_type_list );
> > > >
> > > > return MI_CMD_DONE;
> > > > }
> > >
> > >
> > >
> > > > Index: gdb/mi/mi-cmds.c
> > > > ===================================================================
> > >
> > > > Index: gdb/mi/mi-cmds.h
> > > > ===================================================================
> > >
> > > these changes are ok.
> >
> > Great!
> >
> > > > Index: gdb/testsuite/gdb.mi/mi-file.exp
> > > > ===================================================================
> > > > RCS file: /cvs/src/src/gdb/testsuite/gdb.mi/mi-file.exp,v
> > > > retrieving revision 1.1
> > > > diff -w -u -r1.1 mi-file.exp
> > > > --- gdb/testsuite/gdb.mi/mi-file.exp 2 Apr 2003 22:10:35 -0000 1.1
> > > > +++ gdb/testsuite/gdb.mi/mi-file.exp 25 Feb 2004 03:52:36 -0000
> > > > @@ -55,7 +55,7 @@
> > > >
> > > > # get the path and absolute path to the current executable
> > > > mi_gdb_test "111-file-list-exec-source-file" \
> > > > - "111\\\^done,line=\"23\",file=\"${srcfilepath}\",fullname=\"/.*/${srcfile}\"" \
> > > > + "111\\\^done,line=\"23\",filename=\"${srcfilepath}\",fullname=\"/.*/${srcfile}\"" \
> > >
> > > Wouldn't this break existing MI parsers?
> >
> > Yes. I figured it could be mi2. Also, for some reason, I thought no one
> > would be using this function since I wrote it for CGDB, and I haven't
> > used it yet. I have a larger plan in mind for MI, than just these 2
> > commands (-file-list-exec-source-file and -file-list-exec-source-files).
> > I would like to add the fullname to a lot of commands. However, I think
> > 'filename' and 'fullname' should be standardized, so that front end
> > writers immediatly understand what they are. It is awkard to have 1
> > function say "file=" and another say "filename=", when those 2 words
> > mean the same thing.
> >
> > However, if this changes isn't acceptable, I can change it back.
> >
> > > > "request path info of current source file (${srcfile})"
> > > > }
> > > >
> > > > Index: gdb/testsuite/gdb.mi/mi2-file.exp
> > > > ===================================================================
> > > > RCS file: /cvs/src/src/gdb/testsuite/gdb.mi/mi2-file.exp,v
> > > > retrieving revision 1.1
> > > > diff -w -u -r1.1 mi2-file.exp
> > > > --- gdb/testsuite/gdb.mi/mi2-file.exp 7 Aug 2003 17:47:42 -0000 1.1
> > > > +++ gdb/testsuite/gdb.mi/mi2-file.exp 25 Feb 2004 03:52:36 -0000
> > > > @@ -47,7 +47,7 @@
> > > > mi_gdb_reinitialize_dir $srcdir/$subdir
> > > > mi_gdb_load ${binfile}
> > > >
> > > > -proc test_tbreak_creation_and_listing {} {
> > > > +proc test_file_list_exec_source_file {} {
> > > > global srcfile
> > > > global srcdir
> > > > global subdir
> > > > @@ -55,11 +55,21 @@
> > > >
> > > > # get the path and absolute path to the current executable
> > > > mi_gdb_test "111-file-list-exec-source-file" \
> > > > - "111\\\^done,line=\"23\",file=\"${srcfilepath}\",fullname=\"/.*/${srcfile}\"" \
> > > > + "111\\\^done,line=\"23\",filename=\"${srcfilepath}\",fullname=\"/.*/${srcfile}\"" \
> > > > "request path info of current source file (${srcfile})"
> > > > }
> > > >
> > > > -test_tbreak_creation_and_listing
> > > > +proc test_file_list_exec_source_files {} {
> > > > + global srcfile
> > > > +
> > > > + # get the path and absolute path to the current executable
> > > > + mi_gdb_test "222-file-list-exec-source-files" \
> > > > + "222\\\^done,files=\\\[\{filename=\".*/${srcfile}\",fullname=\"/.*/${srcfile}\"\},\{filename=\".*\"\},\{filename=\".*\"\},\{filename=\".*\"\},\{filename=\".*\"\}\\\]" \
> > >
> > > > + "Getting a list of source files failed."
> > > ^^^^^^^
> > > why failed?
> >
> > OOO, That isn't an error condition, it's just a comment. I see.
> >
> > Thanks,
> > Bob Rossi