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-rw-r--r--tools/perf/util/srccode.c172
1 files changed, 172 insertions, 0 deletions
diff --git a/tools/perf/util/srccode.c b/tools/perf/util/srccode.c
new file mode 100644
index 000000000..c29edaaca
--- /dev/null
+++ b/tools/perf/util/srccode.c
@@ -0,0 +1,172 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Manage printing of source lines
+ * Copyright (c) 2017, Intel Corporation.
+ * Author: Andi Kleen
+ */
+#include <linux/list.h>
+#include <linux/zalloc.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <assert.h>
+#include <string.h>
+#include "srccode.h"
+#include "debug.h"
+#include <internal/lib.h> // page_size
+#include "fncache.h"
+
+#define MAXSRCCACHE (32*1024*1024)
+#define MAXSRCFILES 64
+#define SRC_HTAB_SZ 64
+
+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;
+ unsigned hval = shash((unsigned char *)fn) % SRC_HTAB_SZ;
+
+ hlist_for_each_entry (h, &srcfile_htab[hval], hash_nd) {
+ if (!strcmp(fn, h->fn)) {
+ /* Move to front */
+ list_del(&h->nd);
+ list_add(&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) {
+ pr_debug("cannot open source file %s\n", fn);
+ return NULL;
+ }
+
+ h = malloc(sizeof(struct srcfile));
+ if (!h)
+ return NULL;
+
+ h->fn = strdup(fn);
+ if (!h->fn)
+ goto out_h;
+
+ h->maplen = st.st_size;
+ sz = (h->maplen + page_size - 1) & ~(page_size - 1);
+ h->map = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0);
+ close(fd);
+ if (h->map == (char *)-1) {
+ pr_debug("cannot mmap source file %s\n", fn);
+ goto out_fn;
+ }
+ h->numlines = countlines(h->map, h->maplen);
+ h->lines = calloc(h->numlines, sizeof(char *));
+ if (!h->lines)
+ goto out_map;
+ fill_lines(h->lines, h->numlines, h->map, h->maplen);
+ list_add(&h->nd, &srcfile_list);
+ hlist_add_head(&h->hash_nd, &srcfile_htab[hval]);
+ map_total_sz += h->maplen;
+ num_srcfiles++;
+ return h;
+
+out_map:
+ munmap(h->map, sz);
+out_fn:
+ zfree(&h->fn);
+out_h:
+ free(h);
+ return NULL;
+}
+
+/* Result is not 0 terminated */
+char *find_sourceline(char *fn, unsigned line, int *lenp)
+{
+ char *l, *p;
+ struct srcfile *sf = find_srcfile(fn);
+ if (!sf)
+ return NULL;
+ line--;
+ if (line >= sf->numlines)
+ return NULL;
+ l = sf->lines[line];
+ if (!l)
+ return NULL;
+ p = memchr(l, '\n', sf->map + sf->maplen - l);
+ *lenp = p - l;
+ return l;
+}