- Correctly handle sections of type SHT_NOBITS. For these sections:

  - elf_getdata() and elf_rawdata() should return an "Elf_Data" structure
    that has its "d_buf" member set to NULL and "d_size" member set to
    the nominal 'size' of the section.  [1]
  - Update the manual page for these functions.
- Fix a memory leak in an error handling path inside elf_getdata().
- Use _libelf_allocate_data() in elf_newdata() for consistency.

Obtained from:	elftoolchain
MFC after:		1 month

1 files changed, 27 insertions, 1 deletions

diff --git a/lib/libelf/elf_getdata.3 b/lib/libelf/elf_getdata.3
index 10f37639563b..565c77c8a02f 100644
--- a/lib/libelf/elf_getdata.3
+++ b/lib/libelf/elf_getdata.3
@@ -1,4 +1,4 @@
-.\" Copyright (c) 2006 Joseph Koshy.  All rights reserved.
+.\" Copyright (c) 2006,2008 Joseph Koshy.  All rights reserved.
 .\"
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
@@ -142,6 +142,32 @@ always returns
 .Vt Elf_Data
 structures of type
 .Dv ELF_T_BYTE .
+.Ss Special handling of SHT_NOBITS sections
+For sections of type
+.Dv SHT_NOBITS ,
+the functions
+.Fn elf_getdata
+and
+.Fn elf_rawdata
+return a pointer to a valid
+.Vt Elf_Data
+structure that has its
+.Va d_buf
+member set to NULL and its
+.Va d_size
+member set to the size of the section.
+.Pp
+If an application wishes to create a section of type
+.Dv SHT_NOBITS ,
+it should add a data buffer to the section using function
+.Fn elf_newdata .
+It should then set the
+.Va d_buf
+and
+.Va d_size
+members of the returned
+.Vt Elf_Data
+structure to NULL and the desired size of the section respectively.
 .Sh RETURN VALUES
 These functions return a valid pointer to a data descriptor if successful, or
 NULL if an error occurs.