update from main archive 961008
[kopensolaris-gnu/glibc.git] / nss / nss_files / files-parse.c
1 /* Common code for file-based database parsers in nss_files module.
2 Copyright (C) 1996 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13 Library General Public License for more details.
14
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB.  If
17 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
18 Cambridge, MA 02139, USA.  */
19
20 #include <ctype.h>
21 #include <errno.h>
22 #include <string.h>
23 #include <stdlib.h>
24
25 /* These symbols are defined by the including source file:
26
27    ENTNAME -- database name of the structure and functions (hostent, pwent).
28    STRUCTURE -- struct name, define only if not ENTNAME (passwd, group).
29    DATABASE -- string of the database file's name ("hosts", "passwd").
30
31    ENTDATA -- if defined, `struct ENTDATA' is used by the parser to store
32               things pointed to by the resultant `struct STRUCTURE'.
33
34    NEED_H_ERRNO - defined iff an arg `int *herrnop' is used.
35
36    Also see files-XXX.c.  */
37
38 #define CONCAT(a,b) CONCAT1(a,b)
39 #define CONCAT1(a,b) a##b
40
41 #ifndef STRUCTURE
42 #define STRUCTURE ENTNAME
43 #endif
44
45
46 struct parser_data
47   {
48 #ifdef ENTDATA
49     struct ENTDATA entdata;
50 #define ENTDATA_DECL(data) struct ENTDATA *const entdata = &data->entdata;
51 #else
52 #define ENTDATA_DECL(data)
53 #endif
54     char linebuffer[0];
55   };
56
57 #ifdef ENTDATA
58 /* The function can't be exported, because the entdata structure
59    is defined only in files-foo.c.  */
60 #define parser_stclass static inline
61 #else
62 /* Export the line parser function so it can be used in nss_db.  */
63 #define parser_stclass /* Global */
64 #define parse_line CONCAT(_nss_files_parse_,ENTNAME)
65 #endif
66
67
68 #ifdef EXTERN_PARSER
69
70 /* The parser is defined in a different module.  */
71 extern int parse_line (char *line, struct STRUCTURE *result,
72                        struct parser_data *data, int datalen);
73
74 #define LINE_PARSER(EOLSET, BODY) /* Do nothing */
75
76 #else
77
78 /* Define a line parsing function.  */
79
80 #define LINE_PARSER(EOLSET, BODY)                                             \
81 parser_stclass int                                                            \
82 parse_line (char *line, struct STRUCTURE *result,                             \
83             struct parser_data *data, int datalen)                            \
84 {                                                                             \
85   ENTDATA_DECL (data)                                                         \
86   char *p = strpbrk (line, EOLSET "\n");                                      \
87   if (p)                                                                      \
88     *p = '\0';                                                                \
89   BODY;                                                                       \
90   TRAILING_LIST_PARSER;                                                       \
91   return 1;                                                                   \
92 }
93
94
95 #define STRING_FIELD(variable, terminator_p, swallow)                         \
96   {                                                                           \
97     variable = line;                                                          \
98     while (*line != '\0' && !terminator_p (*line))                            \
99       ++line;                                                                 \
100     if (*line != '\0')                                                        \
101       {                                                                       \
102         *line = '\0';                                                         \
103         do                                                                    \
104           ++line;                                                             \
105         while (swallow && terminator_p (*line));                              \
106       }                                                                       \
107   }
108
109 #define INT_FIELD(variable, terminator_p, swallow, base, convert)             \
110   {                                                                           \
111     char *endp;                                                               \
112     variable = convert (strtol (line, &endp, base));                          \
113     if (endp == line)                                                         \
114       return 0;                                                               \
115     else if (terminator_p (*endp))                                            \
116       do                                                                      \
117         ++endp;                                                               \
118       while (swallow && terminator_p (*endp));                                \
119     else if (*endp != '\0')                                                   \
120       return 0;                                                               \
121     line = endp;                                                              \
122   }
123
124 #define INT_FIELD_MAYBE_NULL(variable, terminator_p, swallow, base, convert, default)         \
125   {                                                                           \
126     char *endp;                                                               \
127     if (*line == '\0')                                                        \
128       /* We expect some more input, so don't allow the string to end here. */ \
129       return 0;                                                               \
130     variable = convert (strtol (line, &endp, base));                          \
131     if (endp == line)                                                         \
132       variable = default;                                                     \
133     if (terminator_p (*endp))                                                 \
134       do                                                                      \
135         ++endp;                                                               \
136       while (swallow && terminator_p (*endp));                                \
137     else if (*endp != '\0')                                                   \
138       return 0;                                                               \
139     line = endp;                                                              \
140   }
141
142 #define ISCOLON(c) ((c) == ':')
143
144
145 #ifndef TRAILING_LIST_MEMBER
146 #define TRAILING_LIST_PARSER /* Nothing to do.  */
147 #else
148
149 #define TRAILING_LIST_PARSER                                                  \
150 {                                                                             \
151   char **list = parse_list (line, data, datalen);                             \
152   if (list)                                                                   \
153     result->TRAILING_LIST_MEMBER = list;                                      \
154   else                                                                        \
155     return 0;                                                                 \
156 }
157
158 static inline char **
159 parse_list (char *line, struct parser_data *data, int datalen)
160 {
161   char *eol, **list, **p;
162
163   if (line >= data->linebuffer && line < (char *) data + datalen)
164     /* Find the end of the line buffer, we will use the space in DATA after
165        it for storing the vector of pointers.  */
166     eol = strchr (line, '\0') + 1;
167   else
168     /* LINE does not point within DATA->linebuffer, so that space is
169        not being used for scratch space right now.  We can use all of
170        it for the pointer vector storage.  */
171     eol = data->linebuffer;
172   /* Adjust the pointer so it is aligned for storing pointers.  */
173   eol += __alignof__ (char *) - 1;
174   eol -= (eol - (char *) 0) % __alignof__ (char *);
175   /* We will start the storage here for the vector of pointers.  */
176   list = (char **) eol;
177
178   p = list;
179   while (1)
180     {
181       char *elt;
182
183       if ((char *) &p[1] - (char *) data > datalen)
184         {
185           /* We cannot fit another pointer in the buffer.  */
186           __set_errno (ERANGE);
187           return NULL;
188         }
189       if (*line == '\0')
190         break;
191
192       elt = line;
193       while (1)
194         {
195           if (TRAILING_LIST_SEPARATOR_P (*line))
196             {
197               *p++ = elt;
198               *line = '\0';
199               do
200                 ++line;
201               while (TRAILING_LIST_SEPARATOR_P (*line));
202               elt = line;
203             }
204           else if (*line == '\0' || *line == '\n')
205             {
206               /* End of the line.  */
207               if (line > elt)
208                 /* Last element.  */
209                 *p++ = elt;
210               *line = '\0';
211               break;
212             }
213           else
214             ++line;
215         }
216     }
217   *p = NULL;
218
219   return list;
220 }
221
222 #endif  /* TRAILING_LIST_MEMBER */
223 #endif  /* EXTERN_PARSER */
224
225
226 #define LOOKUP_NAME(nameelt, aliaselt)                                        \
227 {                                                                             \
228   char **ap;                                                                  \
229   if (! strcmp (name, result->nameelt))                                       \
230     break;                                                                    \
231   for (ap = result->aliaselt; *ap; ++ap)                                      \
232     if (! strcmp (name, *ap))                                                 \
233       break;                                                                  \
234   if (*ap)                                                                    \
235     break;                                                                    \
236 }
237
238
239 /* This is defined by db-*.c to include "../nss_db/db-XXX.c" instead.  */
240 #ifndef GENERIC
241 #define GENERIC "files-XXX.c"
242 #endif