1/*
2
3Copyright (c) 1993, 1994, 1998  The Open Group
4
5Permission to use, copy, modify, distribute, and sell this software and its
6documentation for any purpose is hereby granted without fee, provided that
7the above copyright notice appear in all copies and that both that
8copyright notice and this permission notice appear in supporting
9documentation.
10
11The above copyright notice and this permission notice shall be included in
12all copies or substantial portions of the Software.
13
14THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
17OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
18AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
19CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
20
21Except as contained in this notice, the name of The Open Group shall not be
22used in advertising or otherwise to promote the sale, use or other dealings
23in this Software without prior written authorization from The Open Group.
24
25*/
26
27#include "def.h"
28
29#include "ifparser.h"
30
31struct _parse_data {
32    struct filepointer *filep;
33    struct inclist *inc;
34    const char *filename;
35    const char *line;
36};
37
38static const char *
39my_if_errors(IfParser *ip, const char *cp, const char *expecting)
40{
41    struct _parse_data *pd = ip->data;
42    long lineno = pd->filep->f_line;
43    const char *filename = pd->filename;
44    char prefix[300];
45    long prefixlen;
46    long i;
47
48    snprintf(prefix, sizeof(prefix), "\"%s\":%ld", filename, lineno);
49    prefixlen = (long) strlen(prefix);
50    fprintf(stderr, "%s:  %s", prefix, pd->line);
51    i = cp - pd->line;
52    if (i > 0 && pd->line[i - 1] != '\n') {
53        putc('\n', stderr);
54    }
55    for (i += prefixlen + 3; i > 0; i--) {
56        putc(' ', stderr);
57    }
58    fprintf(stderr, "^--- expecting %s\n", expecting);
59    return NULL;
60}
61
62
63#define MAXNAMELEN 256
64
65static struct symtab **
66lookup_variable(IfParser *ip, const char *var, int len)
67{
68    char tmpbuf[MAXNAMELEN + 1];
69    struct _parse_data *pd = ip->data;
70
71    if (len > MAXNAMELEN)
72        return NULL;
73
74    strncpy(tmpbuf, var, len);
75    tmpbuf[len] = '\0';
76    return isdefined(tmpbuf, pd->inc, NULL);
77}
78
79
80static int
81my_eval_defined(IfParser *ip, const char *var, int len)
82{
83    if (lookup_variable(ip, var, len))
84        return 1;
85    else
86        return 0;
87}
88
89#define isvarfirstletter(ccc) (isalpha(ccc) || (ccc) == '_')
90
91static long
92my_eval_variable(IfParser *ip, const char *var, int len)
93{
94    long val;
95    struct symtab **s;
96
97    s = lookup_variable(ip, var, len);
98    if (!s)
99        return 0;
100    do {
101        var = (*s)->s_value;
102        if (!isvarfirstletter(*var) || !strcmp((*s)->s_name, var))
103            break;
104        s = lookup_variable(ip, var, strlen(var));
105    } while (s);
106
107    var = ParseIfExpression(ip, var, &val);
108    if (var && *var)
109        debug(4, ("extraneous: '%s'\n", var));
110    return val;
111}
112
113int
114cppsetup(const char *filename, const char *line,
115         struct filepointer *filep, struct inclist *inc)
116{
117    struct _parse_data pd = {
118        .filep = filep,
119        .inc = inc,
120        .line = line,
121        .filename = filename
122    };
123    IfParser ip = {
124        .funcs.handle_error = my_if_errors,
125        .funcs.eval_defined = my_eval_defined,
126        .funcs.eval_variable = my_eval_variable,
127        .data = &pd
128    };
129    long val = 0;
130
131    (void) ParseIfExpression(&ip, line, &val);
132    if (val)
133        return IF;
134    else
135        return IFFALSE;
136}
137