From 5acb0315e51af17f24d23c3e420298d06083e7d1 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Fri, 20 Jan 2017 16:46:10 +0300
Subject: [PATCH] pre-process: try find any include that looks like it might
 work

When we're parsing code from other arches, then normally we error out
because we can't find the right include files.  With this code, we just
look for any include with that name and include it.  Also instead of dying
we just keep going.

It prints a lot of garbage output mostly, but some of the warnings still
work.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
 pre-process.c | 125 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 124 insertions(+), 1 deletion(-)

diff --git a/pre-process.c b/pre-process.c
index 3519a0b7..197341c8 100644
--- a/pre-process.c
+++ b/pre-process.c
@@ -35,6 +35,8 @@
 #include <fcntl.h>
 #include <limits.h>
 #include <time.h>
+#include <dirent.h>
+#include <sys/stat.h>
 
 #include "lib.h"
 #include "allocate.h"
@@ -885,6 +887,125 @@ static int free_preprocessor_line(struct token *token)
 	return 1;
 }
 
+const char *find_include(const char *skip, const char *look_for)
+{
+	DIR *dp;
+	struct dirent *entry;
+	struct stat statbuf;
+	const char *ret;
+	char cwd[PATH_MAX];
+	static char buf[PATH_MAX + 1];
+
+	dp = opendir(".");
+	if (!dp)
+		return NULL;
+
+	if (!getcwd(cwd, sizeof(cwd)))
+		return NULL;
+
+	while ((entry = readdir(dp))) {
+		lstat(entry->d_name, &statbuf);
+
+		if (strcmp(entry->d_name, look_for) == 0) {
+			snprintf(buf, sizeof(buf), "%s/%s", cwd, entry->d_name);
+			return buf;
+		}
+
+		if (S_ISDIR(statbuf.st_mode)) {
+			/* Found a directory, but ignore . and .. */
+			if (strcmp(".", entry->d_name) == 0 ||
+			    strcmp("..", entry->d_name) == 0 ||
+			    strcmp(skip, entry->d_name) == 0)
+				continue;
+
+			chdir(entry->d_name);
+			ret = find_include("", look_for);
+			chdir("..");
+			if (ret)
+				return ret;
+		}
+	}
+	closedir(dp);
+
+	return NULL;
+}
+
+const char *search_dir(const char *stop, const char *look_for)
+{
+	char cwd[PATH_MAX];
+	int len;
+	const char *ret;
+
+	if (!getcwd(cwd, sizeof(cwd)))
+		return NULL;
+
+	len = strlen(cwd);
+	while (len >= 0) {
+		ret = find_include(cwd + len + 1, look_for);
+		if (ret)
+			return ret;
+
+		if (strcmp(cwd, stop) == 0 ||
+		    strcmp(cwd, "/usr/include") == 0 ||
+		    strcmp(cwd, "/usr/local/include") == 0 ||
+		    strlen(cwd) <= 10 ||  /* heck...  don't search /usr/lib/ */
+		    strcmp(cwd, "/") == 0)
+			return NULL;
+
+		while (--len >= 0) {
+			if (cwd[len] == '/') {
+				cwd[len] = '\0';
+				break;
+			}
+		}
+
+		chdir("..");
+	}
+	return NULL;
+}
+
+static void use_best_guess_header_file(struct token *token, const char *filename, struct token **list)
+{
+	char cwd[PATH_MAX];
+	char dir_part[PATH_MAX];
+	const char *file_part;
+	const char *include_name;
+	int len;
+
+	if (!filename || filename[0] == '\0')
+		return;
+
+	file_part = filename;
+	while ((filename = strchr(filename, '/'))) {
+		++filename;
+		if (filename[0])
+			file_part = filename;
+	}
+
+	snprintf(dir_part, sizeof(dir_part), "%s", stream_name(token->pos.stream));
+	len = strlen(dir_part);
+	while (--len >= 0) {
+		if (dir_part[len] == '/') {
+			dir_part[len] = '\0';
+			break;
+		}
+	}
+	if (len < 0)
+		sprintf(dir_part, ".");
+
+	if (!getcwd(cwd, sizeof(cwd)))
+		return;
+
+	chdir(dir_part);
+	include_name = search_dir(cwd, file_part);
+	chdir(cwd);
+	if (!include_name)
+		return;
+	sparse_error(token->pos, "using '%s'", include_name);
+
+	try_include("", include_name, strlen(include_name), list, includepath);
+}
+
 static int handle_include_path(struct stream *stream, struct token **list, struct token *token, int how)
 {
 	const char *filename;
@@ -934,7 +1055,9 @@ static int handle_include_path(struct stream *stream, struct token **list, struc
 	if (do_include_path(path, list, token, filename, flen))
 		return 0;
 out:
-	error_die(token->pos, "unable to open '%s'", filename);
+	sparse_error(token->pos, "unable to open '%s'", filename);
+	use_best_guess_header_file(token, filename, list);
+	return 0;
 }
 
 static int handle_include(struct stream *stream, struct token **list, struct token *token)
-- 
2.11.4.GIT