[PATCH 03/10 v2] libdw: Add locking to dwarf_getsrcfiles and dwarf_getsrclines

[Aaron Merey]

        * libdw/dwarf_getsrcfiles.c (dwarf_getsrcfiles): Use dwarf_lock.
        * libdw/dwarf_getsrclines.c (dwarf_getsrclines): Use dwarf_lock.

Signed-off-by: Aaron Merey <ame...@redhat.com>
---
v2 changes: Combined from v1 patches 04/15 and 05/15.

 libdw/dwarf_getsrcfiles.c | 11 +++++++----
 libdw/dwarf_getsrclines.c | 25 +++++++++++++++++++------
 2 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/libdw/dwarf_getsrcfiles.c b/libdw/dwarf_getsrcfiles.c
index 24e4b7d2..3029ce69 100644
--- a/libdw/dwarf_getsrcfiles.c
+++ b/libdw/dwarf_getsrcfiles.c
@@ -47,9 +47,10 @@ dwarf_getsrcfiles (Dwarf_Die *cudie, Dwarf_Files **files, 
size_t *nfiles)
     }
 
   int res = -1;
+  struct Dwarf_CU *const cu = cudie->cu;
+  mutex_lock (cudie->cu->dbg->dwarf_lock);
 
   /* Get the information if it is not already known.  */
-  struct Dwarf_CU *const cu = cudie->cu;
   if (cu->files == NULL)
     {
       /* For split units there might be a simple file table (without lines).
@@ -96,7 +97,10 @@ dwarf_getsrcfiles (Dwarf_Die *cudie, Dwarf_Files **files, 
size_t *nfiles)
          Dwarf_Off debug_line_offset;
          if (__libdw_formptr (stmt_list, IDX_debug_line, DWARF_E_NO_DEBUG_LINE,
                               NULL, &debug_line_offset) == NULL)
-           return -1;
+           {
+             mutex_unlock (cudie->cu->dbg->dwarf_lock);
+             return -1;
+           }
 
          res = __libdw_getsrcfiles (cu->dbg, debug_line_offset,
                                     __libdw_getcompdir (cudie),
@@ -115,8 +119,7 @@ dwarf_getsrcfiles (Dwarf_Die *cudie, Dwarf_Files **files, 
size_t *nfiles)
        *nfiles = cu->files->nfiles;
     }
 
-  // XXX Eventually: unlocking here.
-
+  mutex_unlock (cudie->cu->dbg->dwarf_lock);
   return res;
 }
 INTDEF (dwarf_getsrcfiles)
diff --git a/libdw/dwarf_getsrclines.c b/libdw/dwarf_getsrclines.c
index b0b5f2eb..79b672dd 100644
--- a/libdw/dwarf_getsrclines.c
+++ b/libdw/dwarf_getsrclines.c
@@ -1444,8 +1444,10 @@ dwarf_getsrclines (Dwarf_Die *cudie, Dwarf_Lines 
**lines, size_t *nlines)
       return -1;
     }
 
-  /* Get the information if it is not already known.  */
   struct Dwarf_CU *const cu = cudie->cu;
+  mutex_lock (cu->dbg->dwarf_lock);
+
+  /* Get the information if it is not already known.  */
   if (cu->lines == NULL)
     {
       /* For split units always pick the lines from the skeleton.  */
@@ -1466,10 +1468,13 @@ dwarf_getsrclines (Dwarf_Die *cudie, Dwarf_Lines 
**lines, size_t *nlines)
                  *lines = cu->lines;
                  *nlines = cu->lines->nlines;
                }
+
+             mutex_unlock (cu->dbg->dwarf_lock);
              return res;
            }
 
          __libdw_seterrno (DWARF_E_NO_DEBUG_LINE);
+         mutex_unlock (cu->dbg->dwarf_lock);
          return -1;
        }
 
@@ -1487,21 +1492,29 @@ dwarf_getsrclines (Dwarf_Die *cudie, Dwarf_Lines 
**lines, size_t *nlines)
       Dwarf_Off debug_line_offset;
       if (__libdw_formptr (stmt_list, IDX_debug_line, DWARF_E_NO_DEBUG_LINE,
                           NULL, &debug_line_offset) == NULL)
-       return -1;
+       {
+         mutex_unlock (cu->dbg->dwarf_lock);
+         return -1;
+       }
 
       if (__libdw_getsrclines (cu->dbg, debug_line_offset,
                               __libdw_getcompdir (cudie),
                               cu->address_size, &cu->lines, &cu->files) < 0)
-       return -1;
+       {
+         mutex_unlock (cu->dbg->dwarf_lock);
+         return -1;
+       }
     }
   else if (cu->lines == (void *) -1l)
-    return -1;
+    {
+      mutex_unlock (cu->dbg->dwarf_lock);
+      return -1;
+    }
 
   *lines = cu->lines;
   *nlines = cu->lines->nlines;
 
-  // XXX Eventually: unlocking here.
-
+  mutex_unlock (cu->dbg->dwarf_lock);
   return 0;
 }
 INTDEF(dwarf_getsrclines)
-- 
2.48.1