From 23e46b680f6fa6fce45aaf6c004cab6be322fbf1 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Fri, 14 Jul 2023 09:35:03 -0600 Subject: [PATCH] Revert "Simplify auto_load_expand_dir_vars and remove substitute_path_component" This reverts commit 02601231fdd91a7bd4837ce202906ea2ce661489. This commit was a refactoring to remove an xrealloc and simplify utils.[ch]. However, it has a flaw -- it mishandles a substitution like "$datadir/subdir". I am backing out the patch in the interests of fixing the regression before GDB 14. It can be reinstated (with modifications) later if we like. Regression tested on x86-64 Fedora 36. --- gdb/Makefile.in | 1 + gdb/auto-load.c | 33 +++++++----------- gdb/unittests/utils-selftests.c | 60 +++++++++++++++++++++++++++++++++ gdb/utils.c | 45 +++++++++++++++++++++++++ gdb/utils.h | 3 ++ 5 files changed, 121 insertions(+), 21 deletions(-) create mode 100644 gdb/unittests/utils-selftests.c diff --git a/gdb/Makefile.in b/gdb/Makefile.in index d909786792c..8521e8d11c8 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -490,6 +490,7 @@ SELFTESTS_SRCS = \ unittests/ui-file-selftests.c \ unittests/unique_xmalloc_ptr_char.c \ unittests/unpack-selftests.c \ + unittests/utils-selftests.c \ unittests/vec-utils-selftests.c \ unittests/xml-utils-selftests.c diff --git a/gdb/auto-load.c b/gdb/auto-load.c index 9d6fabe6bbc..5267cb4e64d 100644 --- a/gdb/auto-load.c +++ b/gdb/auto-load.c @@ -173,33 +173,24 @@ static std::string auto_load_safe_path = AUTO_LOAD_SAFE_PATH; counterpart. */ static std::vector> auto_load_safe_path_vec; -/* Expand $datadir and $debugdir in STRING. */ +/* Expand $datadir and $debugdir in STRING according to the rules of + substitute_path_component. */ static std::vector> auto_load_expand_dir_vars (const char *string) { - std::vector> result - = dirnames_to_char_ptr_vec (string); + char *s = xstrdup (string); + substitute_path_component (&s, "$datadir", gdb_datadir.c_str ()); + substitute_path_component (&s, "$debugdir", debug_file_directory.c_str ()); - for (auto &elt : result) - { - if (strcmp (elt.get (), "$datadir") == 0) - { - elt = make_unique_xstrdup (gdb_datadir.c_str ()); - if (debug_auto_load) - auto_load_debug_printf ("Expanded $datadir to \"%s\".", - gdb_datadir.c_str ()); - } - else if (strcmp (elt.get (), "$debugdir") == 0) - { - elt = make_unique_xstrdup (debug_file_directory.c_str ()); - if (debug_auto_load) - auto_load_debug_printf ("Expanded $debugdir to \"%s\".", - debug_file_directory.c_str ()); - } - } + if (debug_auto_load && strcmp (s, string) != 0) + auto_load_debug_printf ("Expanded $-variables to \"%s\".", s); + + std::vector> dir_vec + = dirnames_to_char_ptr_vec (s); + xfree(s); - return result; + return dir_vec; } /* Update auto_load_safe_path_vec from current AUTO_LOAD_SAFE_PATH. */ diff --git a/gdb/unittests/utils-selftests.c b/gdb/unittests/utils-selftests.c new file mode 100644 index 00000000000..70609aa4294 --- /dev/null +++ b/gdb/unittests/utils-selftests.c @@ -0,0 +1,60 @@ +/* Unit tests for the utils.c file. + + Copyright (C) 2018-2023 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +#include "defs.h" +#include "utils.h" +#include "gdbsupport/selftest.h" + +namespace selftests { +namespace utils { + +static void +test_substitute_path_component () +{ + auto test = [] (std::string s, const char *from, const char *to, + const char *expected) + { + char *temp = xstrdup (s.c_str ()); + substitute_path_component (&temp, from, to); + SELF_CHECK (strcmp (temp, expected) == 0); + xfree (temp); + }; + + test ("/abc/$def/g", "abc", "xyz", "/xyz/$def/g"); + test ("abc/$def/g", "abc", "xyz", "xyz/$def/g"); + test ("/abc/$def/g", "$def", "xyz", "/abc/xyz/g"); + test ("/abc/$def/g", "g", "xyz", "/abc/$def/xyz"); + test ("/abc/$def/g", "ab", "xyz", "/abc/$def/g"); + test ("/abc/$def/g", "def", "xyz", "/abc/$def/g"); + test ("/abc/$def/g", "abc", "abc", "/abc/$def/g"); + test ("/abc/$def/g", "abc", "", "//$def/g"); + test ("/abc/$def/g", "abc/$def", "xyz", "/xyz/g"); + test ("/abc/$def/abc", "abc", "xyz", "/xyz/$def/xyz"); +} + +} +} + +void _initialize_utils_selftests (); +void +_initialize_utils_selftests () +{ + selftests::register_test ("substitute_path_component", + selftests::utils::test_substitute_path_component); +} diff --git a/gdb/utils.c b/gdb/utils.c index 46bfd9a5bbb..cacd6cbd23e 100644 --- a/gdb/utils.c +++ b/gdb/utils.c @@ -3346,6 +3346,51 @@ parse_pid_to_attach (const char *args) return pid; } +/* Substitute all occurrences of string FROM by string TO in *STRINGP. *STRINGP + must come from xrealloc-compatible allocator and it may be updated. FROM + needs to be delimited by IS_DIR_SEPARATOR or DIRNAME_SEPARATOR (or be + located at the start or end of *STRINGP. */ + +void +substitute_path_component (char **stringp, const char *from, const char *to) +{ + char *string = *stringp, *s; + const size_t from_len = strlen (from); + const size_t to_len = strlen (to); + + for (s = string;;) + { + s = strstr (s, from); + if (s == NULL) + break; + + if ((s == string || IS_DIR_SEPARATOR (s[-1]) + || s[-1] == DIRNAME_SEPARATOR) + && (s[from_len] == '\0' || IS_DIR_SEPARATOR (s[from_len]) + || s[from_len] == DIRNAME_SEPARATOR)) + { + char *string_new; + + string_new + = (char *) xrealloc (string, (strlen (string) + to_len + 1)); + + /* Relocate the current S pointer. */ + s = s - string + string_new; + string = string_new; + + /* Replace from by to. */ + memmove (&s[to_len], &s[from_len], strlen (&s[from_len]) + 1); + memcpy (s, to, to_len); + + s += to_len; + } + else + s++; + } + + *stringp = string; +} + #ifdef HAVE_WAITPID #ifdef SIGALRM diff --git a/gdb/utils.h b/gdb/utils.h index 3faac20ec0f..ad0a86746b8 100644 --- a/gdb/utils.h +++ b/gdb/utils.h @@ -136,6 +136,9 @@ private: extern int gdb_filename_fnmatch (const char *pattern, const char *string, int flags); +extern void substitute_path_component (char **stringp, const char *from, + const char *to); + std::string ldirname (const char *filename); extern int count_path_elements (const char *path); -- 2.30.2