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     (200)
24 static int srcfile_depth; /* = 0 */
25 
get_dirname(const char * path)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 
set_initial_path(char * fname)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 
shorten_to_initial_path(char * fname)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  */
try_open(const char * dirname,const char * fname,FILE ** fp)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  */
fopen_any_on_path(const char * fname,FILE ** fp)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 
srcfile_relative_open(const char * fname,char ** fullnamep)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 
srcfile_push(const char * fname)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 
srcfile_pop(void)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 
srcfile_add_search_path(const char * dirname)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 
srcpos_update(struct srcpos * pos,const char * text,int len)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 *
srcpos_copy(struct srcpos * pos)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 
srcpos_extend(struct srcpos * pos,struct srcpos * newtail)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 *
srcpos_string(struct srcpos * pos)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 *
srcpos_string_comment(struct srcpos * pos,bool first_line,int level)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 
srcpos_string_first(struct srcpos * pos,int level)363 char *srcpos_string_first(struct srcpos *pos, int level)
364 {
365 	return srcpos_string_comment(pos, true, level);
366 }
367 
srcpos_string_last(struct srcpos * pos,int level)368 char *srcpos_string_last(struct srcpos *pos, int level)
369 {
370 	return srcpos_string_comment(pos, false, level);
371 }
372 
srcpos_verror(struct srcpos * pos,const char * prefix,const char * fmt,va_list va)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 
srcpos_error(struct srcpos * pos,const char * prefix,const char * fmt,...)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 
srcpos_set_line(char * f,int l)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 }
407