From patchwork Sat Jan 28 03:37:48 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aaron Merey X-Patchwork-Id: 63842 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 063EE3858438 for ; Sat, 28 Jan 2023 03:38:27 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 063EE3858438 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1674877107; bh=BM+AELHUctSN/c/F1YaBMU2i/oGPjW0iLD/jr5VQIso=; h=To:Cc:Subject:Date:List-Id:List-Unsubscribe:List-Archive: List-Post:List-Help:List-Subscribe:From:Reply-To:From; b=no3KHkBnROPfyJXLHcOBprT+kEt5APsD5wKpGh1QEkhToRc8uP1umNNnkRE3g3cMc aAYB0SlWFRDKcd7zHT6K6IjfAE7NOSLedi8vAZGqbAQdsA7YUw/jw8P8YU3anDPnkP SZi9pJ3qOZo7v6yCRCetzTAfqvPlOUJDVx63eefU= X-Original-To: gdb-patches@sourceware.org Delivered-To: gdb-patches@sourceware.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id 2C6C83858C20 for ; Sat, 28 Jan 2023 03:38:03 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 2C6C83858C20 Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-356-EHyg7nxsPkSF3dKgo_3LkQ-1; Fri, 27 Jan 2023 22:38:01 -0500 X-MC-Unique: EHyg7nxsPkSF3dKgo_3LkQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6F42A29A9CAB; Sat, 28 Jan 2023 03:38:01 +0000 (UTC) Received: from localhost.localdomain (unknown [10.22.9.8]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1D0BC40C2064; Sat, 28 Jan 2023 03:38:00 +0000 (UTC) To: gdb-patches@sourceware.org Cc: simark@simark.ca, Aaron Merey Subject: [PATCH] gdb/source: Fix open_source_file error handling Date: Fri, 27 Jan 2023 22:37:48 -0500 Message-Id: <20230128033748.2839360-1-amerey@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-16.7 required=5.0 tests=BAYES_00, DKIM_INVALID, DKIM_SIGNED, GIT_PATCH_0, KAM_DMARC_NONE, KAM_DMARC_STATUS, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Aaron Merey via Gdb-patches From: Aaron Merey Reply-To: Aaron Merey Errors-To: gdb-patches-bounces+patchwork=sourceware.org@sourceware.org Sender: "Gdb-patches" open_source_file relies on errno to communicate the reason for a missing source file. open_source_file also may call debuginfod_find_source. It is possible for debuginfod_find_source to set errno to a value unrelated to the reason for a failed download. This can result in bogus error messages being reported as the reason for a missing source file. The following error message should instead include "No such file or directory": Temporary breakpoint 1, 0x00005555556f4de0 in main () (gdb) list Downloading source file /usr/src/debug/glibc-2.36-8.fc37.x86_64/elf/ 1 /usr/src/debug/glibc-2.36-8.fc37.x86_64/elf/: Directory not empty. Fix this by having open_source_file return a negative errno if it fails to open a source file. Use this value to generate the error message instead of errno. Also add new function throw_sys_errmsg for reporting this value. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29999 --- gdb/source-cache.c | 2 +- gdb/source.c | 40 ++++++++++++++++++++++++++++++---------- gdb/source.h | 5 +++-- gdb/utils.c | 15 +++++++++++++++ gdb/utils.h | 2 ++ 5 files changed, 51 insertions(+), 13 deletions(-) diff --git a/gdb/source-cache.c b/gdb/source-cache.c index b7410d46293..9759fabd45e 100644 --- a/gdb/source-cache.c +++ b/gdb/source-cache.c @@ -95,7 +95,7 @@ source_cache::get_plain_source_lines (struct symtab *s, { scoped_fd desc (open_source_file (s)); if (desc.get () < 0) - perror_with_name (symtab_to_filename_for_display (s)); + throw_sys_errmsg (symtab_to_filename_for_display (s), -desc.get ()); struct stat st; if (fstat (desc.get (), &st) < 0) diff --git a/gdb/source.c b/gdb/source.c index be5af180c49..158b59fd613 100644 --- a/gdb/source.c +++ b/gdb/source.c @@ -1069,7 +1069,7 @@ find_and_open_source (const char *filename, the attempt to read this source file failed. GDB will then display the filename and line number instead. */ if (!source_open) - return scoped_fd (-1); + return scoped_fd (-ECANCELED); /* Quick way out if we already know its full name. */ if (*fullname) @@ -1160,11 +1160,15 @@ find_and_open_source (const char *filename, OPEN_MODE, fullname); } + /* If the file wasn't found, then openp will have set errno accordingly. */ + if (result < 0) + result = -errno; + return scoped_fd (result); } /* Open a source file given a symtab S. Returns a file descriptor or - negative number for error. + negative errno for error. This function is a convenience function to find_and_open_source. */ @@ -1172,7 +1176,7 @@ scoped_fd open_source_file (struct symtab *s) { if (!s) - return scoped_fd (-1); + return scoped_fd (-EINVAL); gdb::unique_xmalloc_ptr fullname (s->fullname); s->fullname = NULL; @@ -1200,10 +1204,21 @@ open_source_file (struct symtab *s) /* Query debuginfod for the source file. */ if (build_id != nullptr && !srcpath.empty ()) - fd = debuginfod_source_query (build_id->data, - build_id->size, - srcpath.c_str (), - &fullname); + { + scoped_fd query_fd + = debuginfod_source_query (build_id->data, + build_id->size, + srcpath.c_str (), + &fullname); + + /* Don't return a negative errno from debuginfod_source_query. + It handles the reporting of its own errors. */ + if (query_fd.get () >= 0) + { + s->fullname = fullname.release (); + return query_fd; + } + } } } @@ -1306,6 +1321,7 @@ print_source_lines_base (struct symtab *s, int line, int stopline, print_source_lines_flags flags) { bool noprint = false; + int errcode = ENOENT; int nlines = stopline - line; struct ui_out *uiout = current_uiout; @@ -1336,7 +1352,10 @@ print_source_lines_base (struct symtab *s, int line, int stopline, scoped_fd desc = open_source_file (s); last_source_error = desc.get () < 0; if (last_source_error) - noprint = true; + { + noprint = true; + errcode = -desc.get (); + } } } else @@ -1354,7 +1373,7 @@ print_source_lines_base (struct symtab *s, int line, int stopline, char *name = (char *) alloca (len); xsnprintf (name, len, "%d\t%s", line, filename); - print_sys_errmsg (name, errno); + print_sys_errmsg (name, errcode); } else { @@ -1627,7 +1646,8 @@ search_command_helper (const char *regex, int from_tty, bool forward) scoped_fd desc (open_source_file (loc->symtab ())); if (desc.get () < 0) - perror_with_name (symtab_to_filename_for_display (loc->symtab ())); + throw_sys_errmsg (symtab_to_filename_for_display (loc->symtab ()), + -desc.get ()); int line = (forward ? last_line_listed + 1 diff --git a/gdb/source.h b/gdb/source.h index 61d1bcd883b..dd6f58c579c 100644 --- a/gdb/source.h +++ b/gdb/source.h @@ -67,7 +67,8 @@ extern void init_source_path (void); The caller is responsible for freeing FULLNAME. On Failure - An invalid file descriptor is returned (the return value is negative). + An invalid file descriptor is returned. The value of this file + descriptor is a negative errno indicating the reason for the failure. FULLNAME is set to NULL. */ extern scoped_fd find_and_open_source (const char *filename, const char *dirname, @@ -81,7 +82,7 @@ extern gdb::unique_xmalloc_ptr find_source_or_rewrite (const char *filename, const char *dirname); /* Open a source file given a symtab S. Returns a file descriptor or - negative number for error. */ + negative errno indicating the reason for the failure. */ extern scoped_fd open_source_file (struct symtab *s); extern gdb::unique_xmalloc_ptr rewrite_source_path (const char *path); diff --git a/gdb/utils.c b/gdb/utils.c index 95adbe58e4a..0a5c6a70531 100644 --- a/gdb/utils.c +++ b/gdb/utils.c @@ -670,6 +670,21 @@ print_sys_errmsg (const char *string, int errcode) gdb_printf (gdb_stderr, "%s: %s.\n", string, err); } +/* Same as perror_with_name except that ERRCODE specifies the error + instead of errno. */ + +void +throw_sys_errmsg (const char *string, int errcode) +{ + const char *err = safe_strerror (errcode); + std::string combined = std::string (string) + ": " + err; + + bfd_set_error (bfd_error_no_error); + errno = 0; + + throw_error (GENERIC_ERROR, _("%s."), combined.c_str ()); +} + /* Control C eventually causes this to be called, at a convenient time. */ void diff --git a/gdb/utils.h b/gdb/utils.h index 7865812998e..54a1bc4e476 100644 --- a/gdb/utils.h +++ b/gdb/utils.h @@ -278,6 +278,8 @@ extern void fprintf_symbol (struct ui_file *, const char *, extern void perror_warning_with_name (const char *string); extern void print_sys_errmsg (const char *, int); + +extern void throw_sys_errmsg (const char *, int) ATTRIBUTE_NORETURN; /* Warnings and error messages. */