Change everything to store error code through provided pointer and not
[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, 1997 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 not,
17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18    Boston, MA 02111-1307, 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, size_t datalen, int *errnop);
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, size_t datalen, int *errnop)            \
84 {                                                                             \
85   ENTDATA_DECL (data)                                                         \
86   char *p = strpbrk (line, EOLSET "\n");                                      \
87   if (p != NULL)                                                              \
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, errnop);                     \
152   if (list)                                                                   \
153     result->TRAILING_LIST_MEMBER = list;                                      \
154   else                                                                        \
155     return -1;          /* -1 indicates we ran out of space.  */              \
156 }
157
158 static inline char **
159 parse_list (char *line, struct parser_data *data, size_t datalen, int *errnop)
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 ((size_t) ((char *) &p[1] - (char *) data) > datalen)
184         {
185           /* We cannot fit another pointer in the buffer.  */
186           *errnop = ERANGE;
187           return NULL;
188         }
189       if (*line == '\0')
190         break;
191
192       /* Skip leading white space.  This might not be portable but useful.  */
193       while (isspace (*line))
194         ++line;
195
196       elt = line;
197       while (1)
198         {
199           if (*line == '\0' || TRAILING_LIST_SEPARATOR_P (*line))
200             {
201               /* End of the next entry.  */
202               if (line > elt)
203                 /* We really found some data.  */
204                 *p++ = elt;
205
206               /* Terminate string if necessary.  */
207               if (*line != '\0')
208                 *line++ = '\0';
209               break;
210             }
211           ++line;
212         }
213     }
214   *p = NULL;
215
216   return list;
217 }
218
219 # endif /* TRAILING_LIST_MEMBER */
220 #endif  /* EXTERN_PARSER */
221
222
223 #define LOOKUP_NAME(nameelt, aliaselt)                                        \
224 {                                                                             \
225   char **ap;                                                                  \
226   if (! strcmp (name, result->nameelt))                                       \
227     break;                                                                    \
228   for (ap = result->aliaselt; *ap; ++ap)                                      \
229     if (! strcmp (name, *ap))                                                 \
230       break;                                                                  \
231   if (*ap)                                                                    \
232     break;                                                                    \
233 }
234
235
236 /* This is defined by db-*.c to include "../nss_db/db-XXX.c" instead.  */
237 #ifndef GENERIC
238 # define GENERIC "files-XXX.c"
239 #endif