From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
From: Bruno Larsen <blarsen@redhat.com>
Date: Thu, 23 Sep 2021 11:19:09 -0300
Subject: gdb-rhbz1970741-early-exit-for-empty-debuginfod-url.patch

;;[gdb] Improve early exits for env var in debuginfod-support.c
;;(Tom de Vries)

There's an early exit in libdebuginfod's debuginfod_query_server, which checks
both for:
- getenv (DEBUGINFOD_URLS_ENV_VAR) == NULL, and
- (getenv (DEBUGINFOD_URLS_ENV_VAR))[0] == '\0'.

In debuginfod_source_query and debuginfod_debuginfo_query (which both
end up calling debuginfod_query_server) there are also early exits checking
the same env var, but those just check for NULL.

Make the early exit tests in debuginfod-support.c match those in
libdebuginfod.

gdb/ChangeLog:

2020-11-18  Tom de Vries  <tdevries@suse.de>

	* debuginfod-support.c (debuginfod_source_query)
	(debuginfod_debuginfo_query): Also do early exit if
	"(getenv (DEBUGINFOD_URLS_ENV_VAR))[0] == '\0'".

diff --git a/gdb/debuginfod-support.c b/gdb/debuginfod-support.c
--- a/gdb/debuginfod-support.c
+++ b/gdb/debuginfod-support.c
@@ -98,7 +98,8 @@ debuginfod_source_query (const unsigned char *build_id,
 			 const char *srcpath,
 			 gdb::unique_xmalloc_ptr<char> *destname)
 {
-  if (getenv (DEBUGINFOD_URLS_ENV_VAR) == NULL)
+  const char *urls_env_var = getenv (DEBUGINFOD_URLS_ENV_VAR);
+  if (urls_env_var == NULL || urls_env_var[0] == '\0')
     return scoped_fd (-ENOSYS);
 
   debuginfod_client *c = debuginfod_init ();
@@ -135,7 +136,8 @@ debuginfod_debuginfo_query (const unsigned char *build_id,
 			    const char *filename,
 			    gdb::unique_xmalloc_ptr<char> *destname)
 {
-  if (getenv (DEBUGINFOD_URLS_ENV_VAR) == NULL)
+  const char *urls_env_var = getenv (DEBUGINFOD_URLS_ENV_VAR);
+  if (urls_env_var == NULL || urls_env_var[0] == '\0')
     return scoped_fd (-ENOSYS);
 
   debuginfod_client *c = debuginfod_init ();