summaryrefslogtreecommitdiffstats
path: root/scripts/basic/split-include.c
blob: 459c45276cb1a4288f77f18fe327ae0c6bd312fb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
/*
 * split-include.c
 *
 * Copyright abandoned, Michael Chastain, <mailto:mec@shout.net>.
 * This is a C version of syncdep.pl by Werner Almesberger.
 *
 * This program takes autoconf.h as input and outputs a directory full
 * of one-line include files, merging onto the old values.
 *
 * Think of the configuration options as key-value pairs.  Then there
 * are five cases:
 *
 *    key      old value   new value   action
 *
 *    KEY-1    VALUE-1     VALUE-1     leave file alone
 *    KEY-2    VALUE-2A    VALUE-2B    write VALUE-2B into file
 *    KEY-3    -           VALUE-3     write VALUE-3  into file
 *    KEY-4    VALUE-4     -           write an empty file
 *    KEY-5    (empty)     -           leave old empty file alone
 */

#include <sys/stat.h>
#include <sys/types.h>

#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#define ERROR_EXIT(strExit)						\
    {									\
	const int errnoSave = errno;					\
	fprintf(stderr, "%s: ", str_my_name);				\
	errno = errnoSave;						\
	perror((strExit));						\
	exit(1);							\
    }



int main(int argc, const char * argv [])
{
    const char * str_my_name;
    const char * str_file_autoconf;
    const char * str_dir_config;

    FILE * fp_config;
    FILE * fp_target;
    FILE * fp_find;

    int buffer_size;

    char * line;
    char * old_line;
    char * list_target;
    char * ptarget;

    struct stat stat_buf;

    /* Check arg count. */
    if (argc != 3)
    {
	fprintf(stderr, "%s: wrong number of arguments.\n", argv[0]);
	exit(1);
    }

    str_my_name       = argv[0];
    str_file_autoconf = argv[1];
    str_dir_config    = argv[2];

    /* Find a buffer size. */
    if (stat(str_file_autoconf, &stat_buf) != 0)
	ERROR_EXIT(str_file_autoconf);
    buffer_size = 2 * stat_buf.st_size + 4096;

    /* Allocate buffers. */
    if ( (line        = malloc(buffer_size)) == NULL
    ||   (old_line    = malloc(buffer_size)) == NULL
    ||   (list_target = malloc(buffer_size)) == NULL )
	ERROR_EXIT(str_file_autoconf);

    /* Open autoconfig file. */
    if ((fp_config = fopen(str_file_autoconf, "r")) == NULL)
	ERROR_EXIT(str_file_autoconf);

    /* Make output directory if needed. */
    if (stat(str_dir_config, &stat_buf) != 0)
    {
	if (mkdir(str_dir_config, 0755) != 0)
	    ERROR_EXIT(str_dir_config);
    }

    /* Change to output directory. */
    if (chdir(str_dir_config) != 0)
	ERROR_EXIT(str_dir_config);

    /* Put initial separator into target list. */
    ptarget = list_target;
    *ptarget++ = '\n';

    /* Read config lines. */
    while (fgets(line, buffer_size, fp_config))
    {
	const char * str_config;
	int is_same;
	int itarget;

	if (line[0] != '#')
	    continue;
	if ((str_config = strstr(line, "CONFIG_")) == NULL)
	    continue;

	/* Make the output file name. */
	str_config += sizeof("CONFIG_") - 1;
	for (itarget = 0; !isspace(str_config[itarget]); itarget++)
	{
	    int c = (unsigned char) str_config[itarget];
	    if (isupper(c)) c = tolower(c);
	    if (c == '_')   c = '/';
	    ptarget[itarget] = c;
	}
	ptarget[itarget++] = '.';
	ptarget[itarget++] = 'h';
	ptarget[itarget++] = '\0';

	/* Check for existing file. */
	is_same = 0;
	if ((fp_target = fopen(ptarget, "r")) != NULL)
	{
	    fgets(old_line, buffer_size, fp_target);
	    if (fclose(fp_target) != 0)
		ERROR_EXIT(ptarget);
	    if (!strcmp(line, old_line))
		is_same = 1;
	}

	if (!is_same)
	{
	    /* Auto-create directories. */
	    int islash;
	    for (islash = 0; islash < itarget; islash++)
	    {
		if (ptarget[islash] == '/')
		{
		    ptarget[islash] = '\0';
		    if (stat(ptarget, &stat_buf) != 0
		    &&  mkdir(ptarget, 0755)     != 0)
			ERROR_EXIT( ptarget );
		    ptarget[islash] = '/';
		}
	    }

	    /* Write the file. */
	    if ((fp_target = fopen(ptarget, "w" )) == NULL)
		ERROR_EXIT(ptarget);
	    fputs(line, fp_target);
	    if (ferror(fp_target) || fclose(fp_target) != 0)
		ERROR_EXIT(ptarget);
	}

	/* Update target list */
	ptarget += itarget;
	*(ptarget-1) = '\n';
    }

    /*
     * Close autoconfig file.
     * Terminate the target list.
     */
    if (fclose(fp_config) != 0)
	ERROR_EXIT(str_file_autoconf);
    *ptarget = '\0';

    /*
     * Fix up existing files which have no new value.
     * This is Case 4 and Case 5.
     *
     * I re-read the tree and filter it against list_target.
     * This is crude.  But it avoids data copies.  Also, list_target
     * is compact and contiguous, so it easily fits into cache.
     *
     * Notice that list_target contains strings separated by \n,
     * with a \n before the first string and after the last.
     * fgets gives the incoming names a terminating \n.
     * So by having an initial \n, strstr will find exact matches.
     */

    fp_find = popen("find * -type f -name \"*.h\" -print", "r");
    if (fp_find == 0)
	ERROR_EXIT( "find" );

    line[0] = '\n';
    while (fgets(line+1, buffer_size, fp_find))
    {
	if (strstr(list_target, line) == NULL)
	{
	    /*
	     * This is an old file with no CONFIG_* flag in autoconf.h.
	     */

	    /* First strip the \n. */
	    line[strlen(line)-1] = '\0';

	    /* Grab size. */
	    if (stat(line+1, &stat_buf) != 0)
		ERROR_EXIT(line);

	    /* If file is not empty, make it empty and give it a fresh date. */
	    if (stat_buf.st_size != 0)
	    {
		if ((fp_target = fopen(line+1, "w")) == NULL)
		    ERROR_EXIT(line);
		if (fclose(fp_target) != 0)
		    ERROR_EXIT(line);
	    }
	}
    }

    if (pclose(fp_find) != 0)
	ERROR_EXIT("find");

    return 0;
}
OpenPOWER on IntegriCloud