treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
[sfrench/cifs-2.6.git] / scripts / dtc / srcpos.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2007 Jon Loeliger, Freescale Semiconductor, Inc.
4  */
5
6 #define _GNU_SOURCE
7
8 #include <stdio.h>
9
10 #include "dtc.h"
11 #include "srcpos.h"
12
13 /* A node in our list of directories to search for source/include files */
14 struct search_path {
15         struct search_path *next;       /* next node in list, NULL for end */
16         const char *dirname;            /* name of directory to search */
17 };
18
19 /* This is the list of directories that we search for source files */
20 static struct search_path *search_path_head, **search_path_tail;
21
22 /* Detect infinite include recursion. */
23 #define MAX_SRCFILE_DEPTH     (100)
24 static int srcfile_depth; /* = 0 */
25
26 static char *get_dirname(const char *path)
27 {
28         const char *slash = strrchr(path, '/');
29
30         if (slash) {
31                 int len = slash - path;
32                 char *dir = xmalloc(len + 1);
33
34                 memcpy(dir, path, len);
35                 dir[len] = '\0';
36                 return dir;
37         }
38         return NULL;
39 }
40
41 FILE *depfile; /* = NULL */
42 struct srcfile_state *current_srcfile; /* = NULL */
43 static char *initial_path; /* = NULL */
44 static int initial_pathlen; /* = 0 */
45 static bool initial_cpp = true;
46
47 static void set_initial_path(char *fname)
48 {
49         int i, len = strlen(fname);
50
51         xasprintf(&initial_path, "%s", fname);
52         initial_pathlen = 0;
53         for (i = 0; i != len; i++)
54                 if (initial_path[i] == '/')
55                         initial_pathlen++;
56 }
57
58 static char *shorten_to_initial_path(char *fname)
59 {
60         char *p1, *p2, *prevslash1 = NULL;
61         int slashes = 0;
62
63         for (p1 = fname, p2 = initial_path; *p1 && *p2; p1++, p2++) {
64                 if (*p1 != *p2)
65                         break;
66                 if (*p1 == '/') {
67                         prevslash1 = p1;
68                         slashes++;
69                 }
70         }
71         p1 = prevslash1 + 1;
72         if (prevslash1) {
73                 int diff = initial_pathlen - slashes, i, j;
74                 int restlen = strlen(fname) - (p1 - fname);
75                 char *res;
76
77                 res = xmalloc((3 * diff) + restlen + 1);
78                 for (i = 0, j = 0; i != diff; i++) {
79                         res[j++] = '.';
80                         res[j++] = '.';
81                         res[j++] = '/';
82                 }
83                 strcpy(res + j, p1);
84                 return res;
85         }
86         return NULL;
87 }
88
89 /**
90  * Try to open a file in a given directory.
91  *
92  * If the filename is an absolute path, then dirname is ignored. If it is a
93  * relative path, then we look in that directory for the file.
94  *
95  * @param dirname       Directory to look in, or NULL for none
96  * @param fname         Filename to look for
97  * @param fp            Set to NULL if file did not open
98  * @return allocated filename on success (caller must free), NULL on failure
99  */
100 static char *try_open(const char *dirname, const char *fname, FILE **fp)
101 {
102         char *fullname;
103
104         if (!dirname || fname[0] == '/')
105                 fullname = xstrdup(fname);
106         else
107                 fullname = join_path(dirname, fname);
108
109         *fp = fopen(fullname, "rb");
110         if (!*fp) {
111                 free(fullname);
112                 fullname = NULL;
113         }
114
115         return fullname;
116 }
117
118 /**
119  * Open a file for read access
120  *
121  * If it is a relative filename, we search the full search path for it.
122  *
123  * @param fname Filename to open
124  * @param fp    Returns pointer to opened FILE, or NULL on failure
125  * @return pointer to allocated filename, which caller must free
126  */
127 static char *fopen_any_on_path(const char *fname, FILE **fp)
128 {
129         const char *cur_dir = NULL;
130         struct search_path *node;
131         char *fullname;
132
133         /* Try current directory first */
134         assert(fp);
135         if (current_srcfile)
136                 cur_dir = current_srcfile->dir;
137         fullname = try_open(cur_dir, fname, fp);
138
139         /* Failing that, try each search path in turn */
140         for (node = search_path_head; !*fp && node; node = node->next)
141                 fullname = try_open(node->dirname, fname, fp);
142
143         return fullname;
144 }
145
146 FILE *srcfile_relative_open(const char *fname, char **fullnamep)
147 {
148         FILE *f;
149         char *fullname;
150
151         if (streq(fname, "-")) {
152                 f = stdin;
153                 fullname = xstrdup("<stdin>");
154         } else {
155                 fullname = fopen_any_on_path(fname, &f);
156                 if (!f)
157                         die("Couldn't open \"%s\": %s\n", fname,
158                             strerror(errno));
159         }
160
161         if (depfile)
162                 fprintf(depfile, " %s", fullname);
163
164         if (fullnamep)
165                 *fullnamep = fullname;
166         else
167                 free(fullname);
168
169         return f;
170 }
171
172 void srcfile_push(const char *fname)
173 {
174         struct srcfile_state *srcfile;
175
176         if (srcfile_depth++ >= MAX_SRCFILE_DEPTH)
177                 die("Includes nested too deeply");
178
179         srcfile = xmalloc(sizeof(*srcfile));
180
181         srcfile->f = srcfile_relative_open(fname, &srcfile->name);
182         srcfile->dir = get_dirname(srcfile->name);
183         srcfile->prev = current_srcfile;
184
185         srcfile->lineno = 1;
186         srcfile->colno = 1;
187
188         current_srcfile = srcfile;
189
190         if (srcfile_depth == 1)
191                 set_initial_path(srcfile->name);
192 }
193
194 bool srcfile_pop(void)
195 {
196         struct srcfile_state *srcfile = current_srcfile;
197
198         assert(srcfile);
199
200         current_srcfile = srcfile->prev;
201
202         if (fclose(srcfile->f))
203                 die("Error closing \"%s\": %s\n", srcfile->name,
204                     strerror(errno));
205
206         /* FIXME: We allow the srcfile_state structure to leak,
207          * because it could still be referenced from a location
208          * variable being carried through the parser somewhere.  To
209          * fix this we could either allocate all the files from a
210          * table, or use a pool allocator. */
211
212         return current_srcfile ? true : false;
213 }
214
215 void srcfile_add_search_path(const char *dirname)
216 {
217         struct search_path *node;
218
219         /* Create the node */
220         node = xmalloc(sizeof(*node));
221         node->next = NULL;
222         node->dirname = xstrdup(dirname);
223
224         /* Add to the end of our list */
225         if (search_path_tail)
226                 *search_path_tail = node;
227         else
228                 search_path_head = node;
229         search_path_tail = &node->next;
230 }
231
232 void srcpos_update(struct srcpos *pos, const char *text, int len)
233 {
234         int i;
235
236         pos->file = current_srcfile;
237
238         pos->first_line = current_srcfile->lineno;
239         pos->first_column = current_srcfile->colno;
240
241         for (i = 0; i < len; i++)
242                 if (text[i] == '\n') {
243                         current_srcfile->lineno++;
244                         current_srcfile->colno = 1;
245                 } else {
246                         current_srcfile->colno++;
247                 }
248
249         pos->last_line = current_srcfile->lineno;
250         pos->last_column = current_srcfile->colno;
251 }
252
253 struct srcpos *
254 srcpos_copy(struct srcpos *pos)
255 {
256         struct srcpos *pos_new;
257         struct srcfile_state *srcfile_state;
258
259         if (!pos)
260                 return NULL;
261
262         pos_new = xmalloc(sizeof(struct srcpos));
263         assert(pos->next == NULL);
264         memcpy(pos_new, pos, sizeof(struct srcpos));
265
266         /* allocate without free */
267         srcfile_state = xmalloc(sizeof(struct srcfile_state));
268         memcpy(srcfile_state, pos->file, sizeof(struct srcfile_state));
269         pos_new->file = srcfile_state;
270
271         return pos_new;
272 }
273
274 struct srcpos *srcpos_extend(struct srcpos *pos, struct srcpos *newtail)
275 {
276         struct srcpos *p;
277
278         if (!pos)
279                 return newtail;
280
281         for (p = pos; p->next != NULL; p = p->next);
282         p->next = newtail;
283         return pos;
284 }
285
286 char *
287 srcpos_string(struct srcpos *pos)
288 {
289         const char *fname = "<no-file>";
290         char *pos_str;
291
292         if (pos->file && pos->file->name)
293                 fname = pos->file->name;
294
295
296         if (pos->first_line != pos->last_line)
297                 xasprintf(&pos_str, "%s:%d.%d-%d.%d", fname,
298                           pos->first_line, pos->first_column,
299                           pos->last_line, pos->last_column);
300         else if (pos->first_column != pos->last_column)
301                 xasprintf(&pos_str, "%s:%d.%d-%d", fname,
302                           pos->first_line, pos->first_column,
303                           pos->last_column);
304         else
305                 xasprintf(&pos_str, "%s:%d.%d", fname,
306                           pos->first_line, pos->first_column);
307
308         return pos_str;
309 }
310
311 static char *
312 srcpos_string_comment(struct srcpos *pos, bool first_line, int level)
313 {
314         char *pos_str, *fname, *first, *rest;
315         bool fresh_fname = false;
316
317         if (!pos) {
318                 if (level > 1) {
319                         xasprintf(&pos_str, "<no-file>:<no-line>");
320                         return pos_str;
321                 } else {
322                         return NULL;
323                 }
324         }
325
326         if (!pos->file)
327                 fname = "<no-file>";
328         else if (!pos->file->name)
329                 fname = "<no-filename>";
330         else if (level > 1)
331                 fname = pos->file->name;
332         else {
333                 fname = shorten_to_initial_path(pos->file->name);
334                 if (fname)
335                         fresh_fname = true;
336                 else
337                         fname = pos->file->name;
338         }
339
340         if (level > 1)
341                 xasprintf(&first, "%s:%d:%d-%d:%d", fname,
342                           pos->first_line, pos->first_column,
343                           pos->last_line, pos->last_column);
344         else
345                 xasprintf(&first, "%s:%d", fname,
346                           first_line ? pos->first_line : pos->last_line);
347
348         if (fresh_fname)
349                 free(fname);
350
351         if (pos->next != NULL) {
352                 rest = srcpos_string_comment(pos->next, first_line, level);
353                 xasprintf(&pos_str, "%s, %s", first, rest);
354                 free(first);
355                 free(rest);
356         } else {
357                 pos_str = first;
358         }
359
360         return pos_str;
361 }
362
363 char *srcpos_string_first(struct srcpos *pos, int level)
364 {
365         return srcpos_string_comment(pos, true, level);
366 }
367
368 char *srcpos_string_last(struct srcpos *pos, int level)
369 {
370         return srcpos_string_comment(pos, false, level);
371 }
372
373 void srcpos_verror(struct srcpos *pos, const char *prefix,
374                    const char *fmt, va_list va)
375 {
376         char *srcstr;
377
378         srcstr = srcpos_string(pos);
379
380         fprintf(stderr, "%s: %s ", prefix, srcstr);
381         vfprintf(stderr, fmt, va);
382         fprintf(stderr, "\n");
383
384         free(srcstr);
385 }
386
387 void srcpos_error(struct srcpos *pos, const char *prefix,
388                   const char *fmt, ...)
389 {
390         va_list va;
391
392         va_start(va, fmt);
393         srcpos_verror(pos, prefix, fmt, va);
394         va_end(va);
395 }
396
397 void srcpos_set_line(char *f, int l)
398 {
399         current_srcfile->name = f;
400         current_srcfile->lineno = l;
401
402         if (initial_cpp) {
403                 initial_cpp = false;
404                 set_initial_path(f);
405         }
406 }