[binutils-gdb] dlltool: file name too long

[Alan Modra]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a253bea8995323201b016fe477280c1782688ab4

commit a253bea8995323201b016fe477280c1782688ab4
Author: Jiaying Song <jiaying.song.cn@windriver.com>
Date:   Tue Aug 13 10:31:21 2024 +0800

    dlltool: file name too long
    
    During the execution of the command: i686-w64-mingw32-dlltool
    --input-def $def_filepath --output-delaylib $filepath --dllname qemu.exe
    An error occurred:
    i686-w64-mingw32-dlltool: failed to open temporary head file: ..._w64_mingw32_nativesdk_qemu_8_2_2_build_plugins_libqemu_plugin_api_a_h.s
    
    Due to the path length exceeding the Linux system's file name length
    limit (NAME_MAX=255), the temporary file name generated by the
    i686-w64-mingw32-dlltool command becomes too long to open. To address
    this, a new temporary file name prefix is generated using tmp_prefix =
    prefix_encode ("d", getpid()), ensuring that the file name does not
    exceed the system's length limit.
    
    Signed-off-by: Jiaying Song <jiaying.song.cn@windriver.com>
    Reviewed-by: Alan Modra <amodra@gmail.com>

Diff:
---
 binutils/dlltool.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/binutils/dlltool.c b/binutils/dlltool.c
index d75a99d8b3d..6dc16a9ed84 100644
--- a/binutils/dlltool.c
+++ b/binutils/dlltool.c
@@ -4068,9 +4068,9 @@ main (int ac, char **av)
   if (tmp_prefix == NULL)
     {
       /* If possible use a deterministic prefix.  */
-      if (imp_name || delayimp_name)
+      const char *input = imp_name ? imp_name : delayimp_name;
+      if (input && strlen (input) + 2 <= NAME_MAX)
 	{
-	  const char *input = imp_name ? imp_name : delayimp_name;
 	  tmp_prefix = xmalloc (strlen (input) + 2);
 	  sprintf (tmp_prefix, "%s_", input);
 	  for (i = 0; tmp_prefix[i]; i++)
@@ -4078,9 +4078,7 @@ main (int ac, char **av)
 	      tmp_prefix[i] = '_';
 	}
       else
-	{
-	  tmp_prefix = prefix_encode ("d", getpid ());
-	}
+	tmp_prefix = prefix_encode ("d", getpid ());
     }
 
   mangle_defs ();