libsysprof-analyze: include inode when creating ELF

We want to know the inode of the FD that was mmaped so that we can check
the requested inode when processing the address map from a particular
process.

src/libsysprof-analyze/sysprof-elf-loader.c

@@ -20,6 +20,9 @@
 
 #include "config.h"
 
+#include <fcntl.h>
+#include <sys/stat.h>
+
 #include "sysprof-elf-private.h"
 #include "sysprof-elf-loader-private.h"
 #include "sysprof-strings-private.h"
@@ -285,6 +288,33 @@ sysprof_elf_loader_annotate (SysprofElfLoader      *self,
     sysprof_elf_set_debug_link_elf (elf, get_deepest_debuglink (debug_link_elf));
 }
 
+static gboolean
+get_file_and_inode (const char   *path,
+                    GMappedFile **mapped_file,
+                    guint64      *file_inode)
+{
+  struct stat stbuf;
+  int fd;
+
+  g_assert (path != NULL);
+  g_assert (mapped_file != NULL);
+  g_assert (file_inode != NULL);
+
+  *mapped_file = NULL;
+  *file_inode = 0;
+
+  fd = open (path, O_RDONLY|O_CLOEXEC, 0);
+  if (fd == -1)
+    return FALSE;
+
+  if (fstat (fd, &stbuf) == 0)
+    *file_inode = (guint64)stbuf.st_ino;
+  *mapped_file = g_mapped_file_new_from_fd (fd, FALSE, NULL);
+  close (fd);
+
+  return *mapped_file != NULL;
+}
+
 /**
  * sysprof_elf_loader_load:
  * @self: a #SysprofElfLoader
@@ -333,6 +363,7 @@ sysprof_elf_loader_load (SysprofElfLoader       *self,
       SysprofElf *cached_elf = NULL;
       const char *path = paths[i];
       const char *debug_link;
+      guint64 mapped_file_inode;
 
       if (in_flatpak || in_podman)
         path = container_path = access_path_from_container (path);
@@ -353,8 +384,8 @@ sysprof_elf_loader_load (SysprofElfLoader       *self,
        * store a failure record in the cache so that we don't attempt to load
        * it again.
        */
-      if ((mapped_file = g_mapped_file_new (path, FALSE, NULL)))
-        elf = sysprof_elf_new (path, g_steal_pointer (&mapped_file), &local_error);
+      if (get_file_and_inode (path, &mapped_file, &mapped_file_inode))
+        elf = sysprof_elf_new (path, g_steal_pointer (&mapped_file), mapped_file_inode, &local_error);
 
       g_hash_table_insert (self->cache,
                            g_strdup (path),

src/libsysprof-analyze/sysprof-elf-private.h

@@ -30,6 +30,7 @@ G_DECLARE_FINAL_TYPE (SysprofElf, sysprof_elf, SYSPROF, ELF, GObject)
 
 SysprofElf *sysprof_elf_new                   (const char   *filename,
                                                GMappedFile  *mapped_file,
+                                               guint64       file_inode,
                                                GError      **error);
 gboolean    sysprof_elf_matches               (SysprofElf   *self,
                                                guint64       file_inode,

src/libsysprof-analyze/sysprof-elf.c

@@ -150,6 +150,7 @@ sysprof_elf_init (SysprofElf *self)
 SysprofElf *
 sysprof_elf_new (const char   *filename,
                  GMappedFile  *mapped_file,
+                 guint64       file_inode,
                  GError      **error)
 {
   SysprofElf *self;
@@ -163,6 +164,7 @@ sysprof_elf_new (const char   *filename,
   self = g_object_new (SYSPROF_TYPE_ELF, NULL);
   self->file = g_strdup (filename);
   self->parser = g_steal_pointer (&parser);
+  self->file_inode = file_inode;
 
   return self;
 }