[glibc] nss_files: Use generic result pointer in parse_line

[glibc] nss_files: Use generic result pointer in parse_line

[Florian Weimer]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=9980bf0b307368959cb29f3ca3f7446ad92347f1

commit 9980bf0b307368959cb29f3ca3f7446ad92347f1
Author: Florian Weimer <fweimer@redhat.com>
Date:   Thu Jul 16 16:55:45 2020 +0200

    nss_files: Use generic result pointer in parse_line
    
    As a result, all parse_line functions have the same prototype, except
    for that producing struct hostent.  This change is ABI-compatible, so
    it does not alter the internal GLIBC_PRIVATE ABI (otherwise we should
    probably have renamed the exported functions).
    
    A future change will use this to implement a generict fget*ent_r
    function.
    
    Tested-by: Carlos O'Donell <carlos@redhat.com>
    Reviewed-by: Carlos O'Donell <carlos@redhat.com>

Diff:
---
 include/nss_files.h         | 48 ++++++++++++---------------------------------
 nss/nss_files/files-parse.c |  5 +++--
 2 files changed, 15 insertions(+), 38 deletions(-)

diff --git a/include/nss_files.h b/include/nss_files.h
index 54b354afb3..d0f26815b5 100644
--- a/include/nss_files.h
+++ b/include/nss_files.h
@@ -26,45 +26,21 @@ FILE *__nss_files_fopen (const char *path);
 libc_hidden_proto (__nss_files_fopen)
 
 struct parser_data;
-struct etherent;
-struct group;
-struct netent;
-struct passwd;
-struct protoent;
-struct rpcent;
-struct servent;
-struct sgrp;
-struct spwd;
 
 /* Instances of the parse_line function from
    nss/nss_files/files-parse.c.  */
-extern int _nss_files_parse_etherent (char *line, struct etherent *result,
-                                      struct parser_data *data,
-                                      size_t datalen, int *errnop);
-extern int _nss_files_parse_grent (char *line, struct group *result,
-                                   struct parser_data *data,
-                                   size_t datalen, int *errnop);
-extern int _nss_files_parse_netent (char *line, struct netent *result,
-                                    struct parser_data *data,
-                                    size_t datalen, int *errnop);
-extern int _nss_files_parse_protoent (char *line, struct protoent *result,
-                                      struct parser_data *data,
-                                      size_t datalen, int *errnop);
-extern int _nss_files_parse_pwent (char *line, struct passwd *result,
-                                   struct parser_data *data,
-                                   size_t datalen, int *errnop);
-extern int _nss_files_parse_rpcent (char *line, struct rpcent *result,
-                                    struct parser_data *data,
-                                    size_t datalen, int *errnop);
-extern int _nss_files_parse_servent (char *line, struct servent *result,
-                                     struct parser_data *data,
-                                     size_t datalen, int *errnop);
-extern int _nss_files_parse_sgent (char *line, struct sgrp *result,
-                                   struct parser_data *data,
-                                   size_t datalen, int *errnop);
-extern int _nss_files_parse_spent (char *line, struct spwd *result,
-                                   struct parser_data *data,
-                                   size_t datalen, int *errnop);
+typedef int nss_files_parse_line (char *line, void *result,
+                                  struct parser_data *data,
+                                  size_t datalen, int *errnop);
+extern nss_files_parse_line _nss_files_parse_etherent;
+extern nss_files_parse_line _nss_files_parse_grent;
+extern nss_files_parse_line _nss_files_parse_netent;
+extern nss_files_parse_line _nss_files_parse_protoent;
+extern nss_files_parse_line _nss_files_parse_pwent;
+extern nss_files_parse_line _nss_files_parse_rpcent;
+extern nss_files_parse_line _nss_files_parse_servent;
+extern nss_files_parse_line _nss_files_parse_sgent;
+extern nss_files_parse_line _nss_files_parse_spent;
 
 libnss_files_hidden_proto (_nss_files_parse_etherent)
 libc_hidden_proto (_nss_files_parse_grent)
diff --git a/nss/nss_files/files-parse.c b/nss/nss_files/files-parse.c
index 382028765b..c6cd43babe 100644
--- a/nss/nss_files/files-parse.c
+++ b/nss/nss_files/files-parse.c
@@ -87,7 +87,7 @@ struct parser_data
 #ifdef EXTERN_PARSER
 
 /* The parser is defined in a different module.  */
-extern int parse_line (char *line, struct STRUCTURE *result,
+extern int parse_line (char *line, void *result,
 		       struct parser_data *data, size_t datalen, int *errnop
 		       EXTRA_ARGS_DECL);
 
@@ -99,10 +99,11 @@ extern int parse_line (char *line, struct STRUCTURE *result,
 
 # define LINE_PARSER(EOLSET, BODY)					      \
 parser_stclass int							      \
-parse_line (char *line, struct STRUCTURE *result,			      \
+parse_line (char *line, void *generic_result,				      \
 	    struct parser_data *data, size_t datalen, int *errnop	      \
 	    EXTRA_ARGS_DECL)						      \
 {									      \
+  struct STRUCTURE *result = generic_result;				      \
   ENTDATA_DECL (data)							      \
   BUFFER_PREPARE							      \
   char *p = strpbrk (line, EOLSET "\n");				      \