From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23848 invoked by alias); 25 Jul 2006 16:28:51 -0000 Received: (qmail 23836 invoked by uid 22791); 25 Jul 2006 16:28:48 -0000 X-Spam-Check-By: sourceware.org Received: from nile.gnat.com (HELO nile.gnat.com) (205.232.38.5) by sourceware.org (qpsmtpd/0.31) with ESMTP; Tue, 25 Jul 2006 16:28:38 +0000 Received: from localhost (localhost [127.0.0.1]) by filtered-nile.gnat.com (Postfix) with ESMTP id E3A7A48CDCB for ; Tue, 25 Jul 2006 12:28:35 -0400 (EDT) Received: from nile.gnat.com ([127.0.0.1]) by localhost (nile.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 27928-01-6 for ; Tue, 25 Jul 2006 12:28:35 -0400 (EDT) Received: from takamaka.act-europe.fr (unknown [70.71.0.212]) by nile.gnat.com (Postfix) with ESMTP id C5EFC48CDCA for ; Tue, 25 Jul 2006 12:28:34 -0400 (EDT) Received: by takamaka.act-europe.fr (Postfix, from userid 507) id C2BFB47EFA; Tue, 25 Jul 2006 09:28:29 -0700 (PDT) Date: Tue, 25 Jul 2006 16:28:00 -0000 From: Joel Brobecker To: gdb-patches@sources.redhat.com Subject: Re: [RFA] set/unset/show substitute-path commands (take 2) Message-ID: <20060725162829.GC12362@adacore.com> References: <20060715054902.GD1393@adacore.com> <20060719181516.GO15273@adacore.com> <20060724202545.GD15759@nevyn.them.org> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="DocE+STaALJfprDB" Content-Disposition: inline In-Reply-To: <20060724202545.GD15759@nevyn.them.org> User-Agent: Mutt/1.4i Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2006-07/txt/msg00386.txt.bz2 --DocE+STaALJfprDB Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-length: 3235 > > /* Quick way out if we already know its full name */ > > + > > if (*fullname) > > { > > + { > > + /* The user may have requested that source paths be rewritten > > + according to substitution rules he provided. If a substitution > > + rule applies to this path, then apply it. */ > > + char *rewritten_fullname = rewrite_source_path (*fullname); > > + > > + if (rewritten_fullname != NULL) > > + { > > + xfree (*fullname); > > + *fullname = rewritten_fullname; > > + } > > + } > > + > > result = open (*fullname, OPEN_MODE); > > if (result >= 0) > > return result; > > You don't need the extra { } here. OK. I used them to reduce the scope of rewritten_fullname to where this variable is actually used, but I can see that it's not very useful. > > +/* If the last character of PATH is a directory separator, then strip it. */ > > + > > +static void > > +strip_trailing_directory_separator (char *path) > > +{ > > + const int last = strlen (path) - 1; > > + > > + if (last < 0) > > + return; /* No stripping is needed if PATH is the empty string. */ > > + > > + if (IS_DIR_SEPARATOR (path[last])) > > + path[last] = '\0'; > > +} > > Is this going to get you in trouble if PATH is "/" ? I can imagine > that happening. I do not think so. In terms of the function itself, no problem, this is reduced to the empty string. In terms of where we do the matching, the function will correctly match anything that starts with '/', and nothing else. I also verified that it's possible to remove that substitution rule using the emtpy string. However, you might prefer us to adjust the UI a bit, and still keep the '/' at the UI level. So add some tweaks to "show substitute-path" and "unset substitute-path" that will handle '/' as well as ''. So instead of having "show sub" print `' -> `/mnt', it will print `/' -> `/mnt'. And "unset sub" will accept both '' and '/' as argument to delete that rule. It seems hardly necessary, but I don't mind adding this (and the corresponding tests in subst.exp). > Casting function types is a good way to get in trouble. In this case, > there's an answer handy: make_cleanup_freeargv. How conveninent, thanks! Adjusted accordingly. * source.c: #include gdb_assert.h. (substitute_path_rule): New struct. (substitute_path_rules): New static global variable. (substitute_path_rule_matches): New function. (get_substitute_path_rule): New function. (rewrite_source_path): New function. (find_and_open_source): Add source path rewriting support. (strip_trailing_directory_separator): New function. (find_substitute_path_rule): New function. (add_substitute_path_rule): New function. (delete_substitute_path_rule): New function. (show_substitute_path_command): New function. (unset_substitute_path_command): New function. (set_substitute_path_command): New function. (_initialize_source): Add new substitute-path commands. * Makefile.in (source.o): Add dependency on gdb_assert.h. Does it look better? Tested on x86-linux. -- Joel --DocE+STaALJfprDB Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="subst.diff" Content-length: 12630 Index: source.c =================================================================== RCS file: /cvs/src/src/gdb/source.c,v retrieving revision 1.75 diff -u -p -r1.75 source.c --- source.c 15 May 2006 15:50:13 -0000 1.75 +++ source.c 25 Jul 2006 16:01:19 -0000 @@ -29,6 +29,7 @@ #include "gdbcmd.h" #include "frame.h" #include "value.h" +#include "gdb_assert.h" #include #include "gdb_string.h" @@ -73,6 +74,17 @@ static void show_directories (char *, in char *source_path; +/* Support for source path substitution commands. */ + +struct substitute_path_rule +{ + char *from; + char *to; + struct substitute_path_rule *next; +}; + +static struct substitute_path_rule *substitute_path_rules = NULL; + /* Symtab of default file for listing lines of. */ static struct symtab *current_source_symtab; @@ -828,6 +840,85 @@ source_full_path_of (char *filename, cha return 1; } +/* Return non-zero if RULE matches PATH, that is if the rule can be + applied to PATH. */ + +static int +substitute_path_rule_matches (const struct substitute_path_rule *rule, + const char *path) +{ + const int from_len = strlen (rule->from); + const int path_len = strlen (path); + char *path_start; + + if (path_len < from_len) + return 0; + + /* The substitution rules are anchored at the start of the path, + so the path should start with rule->from. There is no filename + comparison routine, so we need to extract the first FROM_LEN + characters from PATH first and use that to do the comparison. */ + + path_start = alloca (from_len + 1); + strncpy (path_start, path, from_len); + path_start[from_len] = '\0'; + + if (FILENAME_CMP (path_start, rule->from) != 0) + return 0; + + /* Make sure that the region in the path that matches the substitution + rule is immediately followed by a directory separator (or the end of + string character). */ + + if (path[from_len] != '\0' && !IS_DIR_SEPARATOR (path[from_len])) + return 0; + + return 1; +} + +/* Find the substitute-path rule that applies to PATH and return it. + Return NULL if no rule applies. */ + +static struct substitute_path_rule * +get_substitute_path_rule (const char *path) +{ + struct substitute_path_rule *rule = substitute_path_rules; + + while (rule != NULL && !substitute_path_rule_matches (rule, path)) + rule = rule->next; + + return rule; +} + +/* If the user specified a source path substitution rule that applies + to PATH, then apply it and return the new path. This new path must + be deallocated afterwards. + + Return NULL if no substitution rule was specified by the user, + or if no rule applied to the given PATH. */ + +static char * +rewrite_source_path (const char *path) +{ + const struct substitute_path_rule *rule = get_substitute_path_rule (path); + char *new_path; + int from_len; + + if (rule == NULL) + return NULL; + + from_len = strlen (rule->from); + + /* Compute the rewritten path and return it. */ + + new_path = + (char *) xmalloc (strlen (path) + 1 + strlen (rule->to) - from_len); + strcpy (new_path, rule->to); + strcat (new_path, path + from_len); + + return new_path; +} + /* 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 @@ -844,7 +935,7 @@ source_full_path_of (char *filename, cha 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 ) + An invalid file descriptor is returned. ( the return value is negative ) FULLNAME is set to NULL. */ int find_and_open_source (struct objfile *objfile, @@ -857,8 +948,20 @@ find_and_open_source (struct objfile *ob int result; /* Quick way out if we already know its full name */ + if (*fullname) { + /* The user may have requested that source paths be rewritten + according to substitution rules he provided. If a substitution + rule applies to this path, then apply it. */ + char *rewritten_fullname = rewrite_source_path (*fullname); + + if (rewritten_fullname != NULL) + { + xfree (*fullname); + *fullname = rewritten_fullname; + } + result = open (*fullname, OPEN_MODE); if (result >= 0) return result; @@ -869,6 +972,17 @@ find_and_open_source (struct objfile *ob if (dirname != NULL) { + /* If necessary, rewrite the compilation directory name according + to the source path substitution rules specified by the user. */ + + char *rewritten_dirname = rewrite_source_path (dirname); + + if (rewritten_dirname != NULL) + { + make_cleanup (xfree, rewritten_dirname); + dirname = rewritten_dirname; + } + /* Replace a path entry of $cdir with the compilation directory name */ #define cdir_len 5 /* We cast strstr's result in case an ANSIhole has made it const, @@ -1587,6 +1701,220 @@ reverse_search_command (char *regex, int fclose (stream); return; } + +/* If the last character of PATH is a directory separator, then strip it. */ + +static void +strip_trailing_directory_separator (char *path) +{ + const int last = strlen (path) - 1; + + if (last < 0) + return; /* No stripping is needed if PATH is the empty string. */ + + if (IS_DIR_SEPARATOR (path[last])) + path[last] = '\0'; +} + +/* Return the path substitution rule that matches FROM. + Return NULL if no rule matches. */ + +static struct substitute_path_rule * +find_substitute_path_rule (const char *from) +{ + struct substitute_path_rule *rule = substitute_path_rules; + + while (rule != NULL) + { + if (FILENAME_CMP (rule->from, from) == 0) + return rule; + rule = rule->next; + } + + return NULL; +} + +/* Add a new substitute-path rule at the end of the current list of rules. + The new rule will replace FROM into TO. */ + +static void +add_substitute_path_rule (char *from, char *to) +{ + struct substitute_path_rule *rule; + struct substitute_path_rule *new_rule; + + new_rule = xmalloc (sizeof (struct substitute_path_rule)); + new_rule->from = xstrdup (from); + new_rule->to = xstrdup (to); + new_rule->next = NULL; + + /* If the list of rules are empty, then insert the new rule + at the head of the list. */ + + if (substitute_path_rules == NULL) + { + substitute_path_rules = new_rule; + return; + } + + /* Otherwise, skip to the last rule in our list and then append + the new rule. */ + + rule = substitute_path_rules; + while (rule->next != NULL) + rule = rule->next; + + rule->next = new_rule; +} + +/* Remove the given source path substitution rule from the current list + of rules. The memory allocated for that rule is also deallocated. */ + +static void +delete_substitute_path_rule (struct substitute_path_rule *rule) +{ + if (rule == substitute_path_rules) + substitute_path_rules = rule->next; + else + { + struct substitute_path_rule *prev = substitute_path_rules; + + while (prev != NULL && prev->next != rule) + prev = prev->next; + + gdb_assert (prev != NULL); + + prev->next = rule->next; + } + + xfree (rule->from); + xfree (rule->to); + xfree (rule); +} + +/* Implement the "show substitute-path" command. */ + +static void +show_substitute_path_command (char *args, int from_tty) +{ + struct substitute_path_rule *rule = substitute_path_rules; + char **argv; + char *from = NULL; + + argv = buildargv (args); + make_cleanup_freeargv (argv); + + /* We expect zero or one argument. */ + + if (argv != NULL && argv[0] != NULL && argv[1] != NULL) + error (_("Too many arguments in command")); + + if (argv != NULL && argv[0] != NULL) + from = argv[0]; + + /* Print the substitution rules. */ + + if (from != NULL) + printf_filtered + (_("Source path substitution rule matching `%s':\n"), from); + else + printf_filtered (_("List of all source path substitution rules:\n")); + + while (rule != NULL) + { + if (from == NULL || FILENAME_CMP (rule->from, from) == 0) + printf_filtered (" `%s' -> `%s'.\n", rule->from, rule->to); + rule = rule->next; + } +} + +/* Implement the "unset substitute-path" command. */ + +static void +unset_substitute_path_command (char *args, int from_tty) +{ + struct substitute_path_rule *rule = substitute_path_rules; + char **argv = buildargv (args); + char *from = NULL; + int rule_found = 0; + + /* This function takes either 0 or 1 argument. */ + + if (argv != NULL && argv[0] != NULL && argv[1] != NULL) + error (_("Incorrect usage, too many arguments in command")); + + if (argv != NULL && argv[0] != NULL) + from = argv[0]; + + /* If the user asked for all the rules to be deleted, ask him + to confirm and give him a chance to abort before the action + is performed. */ + + if (from == NULL + && !query (_("Delete all source path substitution rules? "))) + error (_("Canceled")); + + /* Delete the rule matching the argument. No argument means that + all rules should be deleted. */ + + while (rule != NULL) + { + struct substitute_path_rule *next = rule->next; + + if (from == NULL || FILENAME_CMP (from, rule->from) == 0) + { + delete_substitute_path_rule (rule); + rule_found = 1; + } + + rule = next; + } + + /* If the user asked for a specific rule to be deleted but + we could not find it, then report an error. */ + + if (from != NULL && !rule_found) + error (_("No substitution rule defined for `%s'"), from); +} + +/* Add a new source path substitution rule. */ + +static void +set_substitute_path_command (char *args, int from_tty) +{ + char *from_path, *to_path; + char **argv; + struct substitute_path_rule *rule; + + argv = buildargv (args); + make_cleanup_freeargv (argv); + + if (argv == NULL || argv[0] == NULL || argv [1] == NULL) + error (_("Incorrect usage, too few arguments in command")); + + if (argv[2] != NULL) + error (_("Incorrect usage, too many arguments in command")); + + if (*(argv[0]) == '\0') + error (_("First argument must be at least one character long")); + + /* Strip any trailing directory separator character in either FROM + or TO. The substitution rule already implicitly contains them. */ + strip_trailing_directory_separator (argv[0]); + strip_trailing_directory_separator (argv[1]); + + /* If a rule with the same "from" was previously defined, then + delete it. This new rule replaces it. */ + + rule = find_substitute_path_rule (argv[0]); + if (rule != NULL) + delete_substitute_path_rule (rule); + + /* Insert the new substitution rule. */ + + add_substitute_path_rule (argv[0], argv[1]); +} + void _initialize_source (void) @@ -1666,4 +1994,19 @@ Show number of source lines gdb will lis NULL, show_lines_to_list, &setlist, &showlist); + + add_cmd ("substitute-path", class_files, set_substitute_path_command, + _("\ +Add a source path substitution rule. If a substitution rule was previously\n\ +set, it is overridden."), &setlist); + + add_cmd ("substitute-path", class_files, unset_substitute_path_command, + _("\ +Remove the current source path substitution rule. This has no effect\n\ +if no path substitution rule was previously specified."), + &unsetlist); + + add_cmd ("substitute-path", class_files, show_substitute_path_command, + _("Show the current source path substitution rule."), + &showlist); } Index: Makefile.in =================================================================== RCS file: /cvs/src/src/gdb/Makefile.in,v retrieving revision 1.822 diff -u -p -r1.822 Makefile.in --- Makefile.in 23 Jun 2006 13:01:05 -0000 1.822 +++ Makefile.in 25 Jul 2006 16:01:21 -0000 @@ -2630,7 +2630,8 @@ source.o: source.c $(defs_h) $(symtab_h) $(command_h) $(source_h) $(gdbcmd_h) $(frame_h) $(value_h) \ $(gdb_string_h) $(gdb_stat_h) $(gdbcore_h) $(gdb_regex_h) \ $(symfile_h) $(objfiles_h) $(annotate_h) $(gdbtypes_h) $(linespec_h) \ - $(filenames_h) $(completer_h) $(ui_out_h) $(readline_h) + $(filenames_h) $(completer_h) $(ui_out_h) $(readline_h) \ + $(gdb_assert_h) sparc64fbsd-nat.o: sparc64fbsd-nat.c $(defs_h) $(regcache_h) $(target_h) \ $(fbsd_nat_h) $(sparc64_tdep_h) $(sparc_nat_h) $(bsd_kvm_h) sparc64fbsd-tdep.o: sparc64fbsd-tdep.c $(defs_h) $(frame_h) \ --DocE+STaALJfprDB--