tools/perf/util/srccode.c

Source file repositories/reference/linux-study-clean/tools/perf/util/srccode.c

File Facts

System
Linux kernel
Corpus path
tools/perf/util/srccode.c
Extension
.c
Size
3493 bytes
Lines
172
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

struct srcfile {
	struct hlist_node hash_nd;
	struct list_head nd;
	char *fn;
	char **lines;
	char *map;
	unsigned numlines;
	size_t maplen;
};

static struct hlist_head srcfile_htab[SRC_HTAB_SZ];
static LIST_HEAD(srcfile_list);
static long map_total_sz;
static int num_srcfiles;

static int countlines(char *map, int maplen)
{
	int numl;
	char *end = map + maplen;
	char *p = map;

	if (maplen == 0)
		return 0;
	numl = 0;
	while (p < end && (p = memchr(p, '\n', end - p)) != NULL) {
		numl++;
		p++;
	}
	if (p < end)
		numl++;
	return numl;
}

static void fill_lines(char **lines, int maxline, char *map, int maplen)
{
	int l;
	char *end = map + maplen;
	char *p = map;

	if (maplen == 0 || maxline == 0)
		return;
	l = 0;
	lines[l++] = map;
	while (p < end && (p = memchr(p, '\n', end - p)) != NULL) {
		if (l >= maxline)
			return;
		lines[l++] = ++p;
	}
	if (p < end)
		lines[l] = p;
}

static void free_srcfile(struct srcfile *sf)
{
	list_del_init(&sf->nd);
	hlist_del(&sf->hash_nd);
	map_total_sz -= sf->maplen;
	munmap(sf->map, sf->maplen);
	zfree(&sf->lines);
	zfree(&sf->fn);
	free(sf);
	num_srcfiles--;
}

static struct srcfile *find_srcfile(char *fn)
{
	struct stat st;
	struct srcfile *h;
	int fd;
	unsigned long sz;
	size_t hval = str_hash(fn) % SRC_HTAB_SZ;

	hlist_for_each_entry (h, &srcfile_htab[hval], hash_nd) {
		if (!strcmp(fn, h->fn)) {
			/* Move to front */
			list_move(&h->nd, &srcfile_list);
			return h;
		}
	}

	/* Only prune if there is more than one entry */
	while ((num_srcfiles > MAXSRCFILES || map_total_sz > MAXSRCCACHE) &&
	       srcfile_list.next != &srcfile_list) {
		assert(!list_empty(&srcfile_list));
		h = list_entry(srcfile_list.prev, struct srcfile, nd);
		free_srcfile(h);
	}

	fd = open(fn, O_RDONLY);
	if (fd < 0 || fstat(fd, &st) < 0) {

Annotation

Implementation Notes