From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 0BB463858D3C for ; Thu, 2 Feb 2023 01:39:08 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 0BB463858D3C Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1675301948; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OLd1Eo8msUekqeRgIj60By05OyGQCL56XZ/GxehH69g=; b=NdEeMx0mo8iQlpXebCHZ/PnM92smphRePpVcc8x1WTGSZsi/qgqTDIy38cnCLJS9tvqak3 vGEVzP+8d9C0dwdAr9mVjoVudpVD4wEpOAvCl17oyWkNqLCdFjz3Ju60MPia47L9Z3eJLH 4j7kuO1HOTZhmO2KFRF8EPFo2eD9B50= 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-443-0lFIx64LN0muIxTLU0P-mg-1; Wed, 01 Feb 2023 20:39:07 -0500 X-MC-Unique: 0lFIx64LN0muIxTLU0P-mg-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 6C55F1C09048 for ; Thu, 2 Feb 2023 01:39:07 +0000 (UTC) Received: from localhost.localdomain (unknown [10.22.10.169]) by smtp.corp.redhat.com (Postfix) with ESMTP id 24E4E404BEC0; Thu, 2 Feb 2023 01:39:07 +0000 (UTC) From: Aaron Merey To: keiths@redhat.com Cc: gdb-patches@sourceware.org, Aaron Merey Subject: [PATCH] gdb/source: Fix open_source_file error handling Date: Wed, 1 Feb 2023 20:38:53 -0500 Message-Id: <20230202013853.119354-1-amerey@redhat.com> In-Reply-To: References: 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 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-16.3 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 List-Id: Hi Keith, On Wed, Feb 1, 2023 at 2:45 PM Keith Seitz wrote: > > On 1/27/23 19:37, Aaron Merey via Gdb-patches wrote: > > +           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.  */ > > I would prefer to see a comment on this behavior with debuginfod_source_query's > description. [Repeating here is fine IMO.] I updated the debuginfod_*_query descriptions in debuginfod-support.h. > > --- 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.  */ > > + > > Should this comment be moved to the decl in utils.h? In such > cases, we normally use "See utils.h." as a comment at the > definition. Done. Thanks, Aaron --- 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 to facilitate reporting this value. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29999 --- gdb/debuginfod-support.h | 15 +++++++++------ gdb/source-cache.c | 2 +- gdb/source.c | 40 ++++++++++++++++++++++++++++++---------- gdb/source.h | 5 +++-- gdb/utils.c | 14 ++++++++++++++ gdb/utils.h | 10 ++++++++++ 6 files changed, 67 insertions(+), 19 deletions(-) diff --git a/gdb/debuginfod-support.h b/gdb/debuginfod-support.h index 542d1688fa1..633600a79da 100644 --- a/gdb/debuginfod-support.h +++ b/gdb/debuginfod-support.h @@ -33,8 +33,9 @@ source file path is `/my/source/foo.c`, then SRC_PATH should be `/my/build/../source/foo.c`. - If the file is successfully retrieved, its path on the local machine - is stored in DESTNAME. If GDB is not built with debuginfod, this + If the file is successfully retrieved, return a file descriptor and store + the file's local path in DESTNAME. If unsuccessful, print an error message + and return a negative errno. If GDB is not built with debuginfod, this function returns -ENOSYS. */ extern scoped_fd @@ -51,8 +52,9 @@ debuginfod_source_query (const unsigned char *build_id, FILENAME should be the name or path of the main binary associated with the separate debug info. It is used for printing messages to the user. - If the file is successfully retrieved, its path on the local machine - is stored in DESTNAME. If GDB is not built with debuginfod, this + If the file is successfully retrieved, return a file descriptor and store + the file's local path in DESTNAME. If unsuccessful, print an error message + and return a negative errno. If GDB is not built with debuginfod, this function returns -ENOSYS. */ extern scoped_fd @@ -69,8 +71,9 @@ debuginfod_debuginfo_query (const unsigned char *build_id, FILENAME should be the name or path associated with the executable. It is used for printing messages to the user. - If the file is successfully retrieved, its path on the local machine - is stored in DESTNAME. If GDB is not built with debuginfod, this + If the file is successfully retrieved, return a file descriptor and store + the file's local path in DESTNAME. If unsuccessful, print an error message + and return a negative errno. If GDB is not built with debuginfod, this function returns -ENOSYS. */ extern scoped_fd debuginfod_exec_query (const unsigned char *build_id, 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..263d0925278 100644 --- a/gdb/utils.c +++ b/gdb/utils.c @@ -670,6 +670,20 @@ print_sys_errmsg (const char *string, int errcode) gdb_printf (gdb_stderr, "%s: %s.\n", string, err); } +/* See utils.h. */ + +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..ef305122505 100644 --- a/gdb/utils.h +++ b/gdb/utils.h @@ -278,6 +278,16 @@ 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); + +/* Print the system error message for ERRCODE, and also mention STRING + as the file name for which the error was encountered. Then return + to command level. + + Same as perror_with_name except that ERRCODE specifies the error + instead of errno. */ + +extern void throw_sys_errmsg (const char *string, int errcode) + ATTRIBUTE_NORETURN; /* Warnings and error messages. */ -- 2.39.1