[PATCH 02/10 v2] dwarf_filesrc.c: Add locking

[Aaron Merey]

        * libdw/dwarf_getsrclines.c (read_srcfiles): Initialize Dwarf
        member.
        * libdw/dwarf_filesrc.c (dwarf_filesrc): Use dwarf_lock.
        * libdw/libdwP.h (struct Dwarf_Files_s): Add Dwarf member.

Signed-off-by: Aaron Merey <ame...@redhat.com>
---
v2 changes: Combined v1 patches 03/15 and 06/15 into one patch.

 libdw/dwarf_filesrc.c     | 13 +++++++++++--
 libdw/dwarf_getsrclines.c |  2 ++
 libdw/libdwP.h            |  1 +
 3 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/libdw/dwarf_filesrc.c b/libdw/dwarf_filesrc.c
index d866ce72..a0881f36 100644
--- a/libdw/dwarf_filesrc.c
+++ b/libdw/dwarf_filesrc.c
@@ -38,14 +38,23 @@ const char *
 dwarf_filesrc (Dwarf_Files *file, size_t idx, Dwarf_Word *mtime,
               Dwarf_Word *length)
 {
-  if (file == NULL || idx >= file->nfiles)
+  if (file == NULL)
     return NULL;
 
+  mutex_lock (file->dbg->dwarf_lock);
+  if (idx >= file->nfiles)
+    {
+      mutex_unlock (file->dbg->dwarf_lock);
+      return NULL;
+    }
+
   if (mtime != NULL)
     *mtime = file->info[idx].mtime;
 
   if (length != NULL)
     *length = file->info[idx].length;
 
-  return file->info[idx].name;
+  const char *res = file->info[idx].name;
+  mutex_unlock (file->dbg->dwarf_lock);
+  return res;
 }
diff --git a/libdw/dwarf_getsrclines.c b/libdw/dwarf_getsrclines.c
index da78db67..b0b5f2eb 100644
--- a/libdw/dwarf_getsrclines.c
+++ b/libdw/dwarf_getsrclines.c
@@ -717,6 +717,7 @@ read_srcfiles (Dwarf *dbg,
   if (unlikely (files == NULL))
     goto no_mem;
 
+  files->dbg = dbg;
   const char **dirs = (void *) &files->info[nfilelist];
 
   struct filelist *fileslist = filelist;
@@ -1198,6 +1199,7 @@ read_srclines (Dwarf *dbg,
                        + (ndirs + 1) * sizeof (char *),
                        1);
 
+      newfiles->dbg = dbg;
 
       /* Copy prevfiles to newfiles.  */
       for (size_t n = 0; n < nprevfiles; n++)
diff --git a/libdw/libdwP.h b/libdw/libdwP.h
index 9d2ffab0..a6bd7e5b 100644
--- a/libdw/libdwP.h
+++ b/libdw/libdwP.h
@@ -305,6 +305,7 @@ struct Dwarf_Abbrev
 /* Files in line information records.  */
 struct Dwarf_Files_s
   {
+    Dwarf *dbg;
     unsigned int ndirs;
     unsigned int nfiles;
     struct Dwarf_Fileinfo_s
-- 
2.48.1