1 files changed, 535 insertions, 0 deletions
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
new file mode 100644
index 000000000..391c1e928
--- /dev/null
+++ b/tools/perf/util/util.c
@@ -0,0 +1,535 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "util.h"
+#include "debug.h"
+#include "event.h"
+#include <api/fs/fs.h>
+#include <sys/stat.h>
+#include <sys/utsname.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <limits.h>
+#include <linux/capability.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/time64.h>
+#include <linux/overflow.h>
+#include <unistd.h>
+#include "cap.h"
+#include "strlist.h"
+#include "string2.h"
+
+/*
+ * XXX We need to find a better place for these things...
+ */
+
+bool perf_singlethreaded = true;
+
+void perf_set_singlethreaded(void)
+{
+	perf_singlethreaded = true;
+}
+
+void perf_set_multithreaded(void)
+{
+	perf_singlethreaded = false;
+}
+
+int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
+int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;
+
+int sysctl__max_stack(void)
+{
+	int value;
+
+	if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
+		sysctl_perf_event_max_stack = value;
+
+	if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
+		sysctl_perf_event_max_contexts_per_stack = value;
+
+	return sysctl_perf_event_max_stack;
+}
+
+bool sysctl__nmi_watchdog_enabled(void)
+{
+	static bool cached;
+	static bool nmi_watchdog;
+	int value;
+
+	if (cached)
+		return nmi_watchdog;
+
+	if (sysctl__read_int("kernel/nmi_watchdog", &value) < 0)
+		return false;
+
+	nmi_watchdog = (value > 0) ? true : false;
+	cached = true;
+
+	return nmi_watchdog;
+}
+
+bool test_attr__enabled;
+
+bool perf_host  = true;
+bool perf_guest = false;
+
+void event_attr_init(struct perf_event_attr *attr)
+{
+	if (!perf_host)
+		attr->exclude_host  = 1;
+	if (!perf_guest)
+		attr->exclude_guest = 1;
+	/* to capture ABI version */
+	attr->size = sizeof(*attr);
+}
+
+int mkdir_p(char *path, mode_t mode)
+{
+	struct stat st;
+	int err;
+	char *d = path;
+
+	if (*d != '/')
+		return -1;
+
+	if (stat(path, &st) == 0)
+		return 0;
+
+	while (*++d == '/');
+
+	while ((d = strchr(d, '/'))) {
+		*d = '\0';
+		err = stat(path, &st) && mkdir(path, mode);
+		*d++ = '/';
+		if (err)
+			return -1;
+		while (*d == '/')
+			++d;
+	}
+	return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
+}
+
+static bool match_pat(char *file, const char **pat)
+{
+	int i = 0;
+
+	if (!pat)
+		return true;
+
+	while (pat[i]) {
+		if (strglobmatch(file, pat[i]))
+			return true;
+
+		i++;
+	}
+
+	return false;
+}
+
+/*
+ * The depth specify how deep the removal will go.
+ * 0       - will remove only files under the 'path' directory
+ * 1 .. x  - will dive in x-level deep under the 'path' directory
+ *
+ * If specified the pat is array of string patterns ended with NULL,
+ * which are checked upon every file/directory found. Only matching
+ * ones are removed.
+ *
+ * The function returns:
+ *    0 on success
+ *   -1 on removal failure with errno set
+ *   -2 on pattern failure
+ */
+static int rm_rf_depth_pat(const char *path, int depth, const char **pat)
+{
+	DIR *dir;
+	int ret;
+	struct dirent *d;
+	char namebuf[PATH_MAX];
+	struct stat statbuf;
+
+	/* Do not fail if there's no file. */
+	ret = lstat(path, &statbuf);
+	if (ret)
+		return 0;
+
+	/* Try to remove any file we get. */
+	if (!(statbuf.st_mode & S_IFDIR))
+		return unlink(path);
+
+	/* We have directory in path. */
+	dir = opendir(path);
+	if (dir == NULL)
+		return -1;
+
+	while ((d = readdir(dir)) != NULL && !ret) {
+
+		if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
+			continue;
+
+		if (!match_pat(d->d_name, pat)) {
+			ret =  -2;
+			break;
+		}
+
+		scnprintf(namebuf, sizeof(namebuf), "%s/%s",
+			  path, d->d_name);
+
+		/* We have to check symbolic link itself */
+		ret = lstat(namebuf, &statbuf);
+		if (ret < 0) {
+			pr_debug("stat failed: %s\n", namebuf);
+			break;
+		}
+
+		if (S_ISDIR(statbuf.st_mode))
+			ret = depth ? rm_rf_depth_pat(namebuf, depth - 1, pat) : 0;
+		else
+			ret = unlink(namebuf);
+	}
+	closedir(dir);
+
+	if (ret < 0)
+		return ret;
+
+	return rmdir(path);
+}
+
+static int rm_rf_a_kcore_dir(const char *path, const char *name)
+{
+	char kcore_dir_path[PATH_MAX];
+	const char *pat[] = {
+		"kcore",
+		"kallsyms",
+		"modules",
+		NULL,
+	};
+
+	snprintf(kcore_dir_path, sizeof(kcore_dir_path), "%s/%s", path, name);
+
+	return rm_rf_depth_pat(kcore_dir_path, 0, pat);
+}
+
+static bool kcore_dir_filter(const char *name __maybe_unused, struct dirent *d)
+{
+	const char *pat[] = {
+		"kcore_dir",
+		"kcore_dir__[1-9]*",
+		NULL,
+	};
+
+	return match_pat(d->d_name, pat);
+}
+
+static int rm_rf_kcore_dir(const char *path)
+{
+	struct strlist *kcore_dirs;
+	struct str_node *nd;
+	int ret;
+
+	kcore_dirs = lsdir(path, kcore_dir_filter);
+
+	if (!kcore_dirs)
+		return 0;
+
+	strlist__for_each_entry(nd, kcore_dirs) {
+		ret = rm_rf_a_kcore_dir(path, nd->s);
+		if (ret)
+			return ret;
+	}
+
+	strlist__delete(kcore_dirs);
+
+	return 0;
+}
+
+int rm_rf_perf_data(const char *path)
+{
+	const char *pat[] = {
+		"data",
+		"data.*",
+		NULL,
+	};
+
+	rm_rf_kcore_dir(path);
+
+	return rm_rf_depth_pat(path, 0, pat);
+}
+
+int rm_rf(const char *path)
+{
+	return rm_rf_depth_pat(path, INT_MAX, NULL);
+}
+
+/* A filter which removes dot files */
+bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
+{
+	return d->d_name[0] != '.';
+}
+
+/* lsdir reads a directory and store it in strlist */
+struct strlist *lsdir(const char *name,
+		      bool (*filter)(const char *, struct dirent *))
+{
+	struct strlist *list = NULL;
+	DIR *dir;
+	struct dirent *d;
+
+	dir = opendir(name);
+	if (!dir)
+		return NULL;
+
+	list = strlist__new(NULL, NULL);
+	if (!list) {
+		errno = ENOMEM;
+		goto out;
+	}
+
+	while ((d = readdir(dir)) != NULL) {
+		if (!filter || filter(name, d))
+			strlist__add(list, d->d_name);
+	}
+
+out:
+	closedir(dir);
+	return list;
+}
+
+size_t hex_width(u64 v)
+{
+	size_t n = 1;
+
+	while ((v >>= 4))
+		++n;
+
+	return n;
+}
+
+int perf_event_paranoid(void)
+{
+	int value;
+
+	if (sysctl__read_int("kernel/perf_event_paranoid", &value))
+		return INT_MAX;
+
+	return value;
+}
+
+bool perf_event_paranoid_check(int max_level)
+{
+	return perf_cap__capable(CAP_SYS_ADMIN) ||
+			perf_cap__capable(CAP_PERFMON) ||
+			perf_event_paranoid() <= max_level;
+}
+
+static int
+fetch_ubuntu_kernel_version(unsigned int *puint)
+{
+	ssize_t len;
+	size_t line_len = 0;
+	char *ptr, *line = NULL;
+	int version, patchlevel, sublevel, err;
+	FILE *vsig;
+
+	if (!puint)
+		return 0;
+
+	vsig = fopen("/proc/version_signature", "r");
+	if (!vsig) {
+		pr_debug("Open /proc/version_signature failed: %s\n",
+			 strerror(errno));
+		return -1;
+	}
+
+	len = getline(&line, &line_len, vsig);
+	fclose(vsig);
+	err = -1;
+	if (len <= 0) {
+		pr_debug("Reading from /proc/version_signature failed: %s\n",
+			 strerror(errno));
+		goto errout;
+	}
+
+	ptr = strrchr(line, ' ');
+	if (!ptr) {
+		pr_debug("Parsing /proc/version_signature failed: %s\n", line);
+		goto errout;
+	}
+
+	err = sscanf(ptr + 1, "%d.%d.%d",
+		     &version, &patchlevel, &sublevel);
+	if (err != 3) {
+		pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
+			 line);
+		goto errout;
+	}
+
+	*puint = (version << 16) + (patchlevel << 8) + sublevel;
+	err = 0;
+errout:
+	free(line);
+	return err;
+}
+
+int
+fetch_kernel_version(unsigned int *puint, char *str,
+		     size_t str_size)
+{
+	struct utsname utsname;
+	int version, patchlevel, sublevel, err;
+	bool int_ver_ready = false;
+
+	if (access("/proc/version_signature", R_OK) == 0)
+		if (!fetch_ubuntu_kernel_version(puint))
+			int_ver_ready = true;
+
+	if (uname(&utsname))
+		return -1;
+
+	if (str && str_size) {
+		strncpy(str, utsname.release, str_size);
+		str[str_size - 1] = '\0';
+	}
+
+	if (!puint || int_ver_ready)
+		return 0;
+
+	err = sscanf(utsname.release, "%d.%d.%d",
+		     &version, &patchlevel, &sublevel);
+
+	if (err != 3) {
+		pr_debug("Unable to get kernel version from uname '%s'\n",
+			 utsname.release);
+		return -1;
+	}
+
+	*puint = (version << 16) + (patchlevel << 8) + sublevel;
+	return 0;
+}
+
+int perf_tip(char **strp, const char *dirpath)
+{
+	struct strlist *tips;
+	struct str_node *node;
+	struct strlist_config conf = {
+		.dirname = dirpath,
+		.file_only = true,
+	};
+	int ret = 0;
+
+	*strp = NULL;
+	tips = strlist__new("tips.txt", &conf);
+	if (tips == NULL)
+		return -errno;
+
+	if (strlist__nr_entries(tips) == 0)
+		goto out;
+
+	node = strlist__entry(tips, random() % strlist__nr_entries(tips));
+	if (asprintf(strp, "Tip: %s", node->s) < 0)
+		ret = -ENOMEM;
+
+out:
+	strlist__delete(tips);
+
+	return ret;
+}
+
+char *perf_exe(char *buf, int len)
+{
+	int n = readlink("/proc/self/exe", buf, len);
+	if (n > 0) {
+		buf[n] = 0;
+		return buf;
+	}
+	return strcpy(buf, "perf");
+}
+
+void perf_debuginfod_setup(struct perf_debuginfod *di)
+{
+	/*
+	 * By default '!di->set' we clear DEBUGINFOD_URLS, so debuginfod
+	 * processing is not triggered, otherwise we set it to 'di->urls'
+	 * value. If 'di->urls' is "system" we keep DEBUGINFOD_URLS value.
+	 */
+	if (!di->set)
+		setenv("DEBUGINFOD_URLS", "", 1);
+	else if (di->urls && strcmp(di->urls, "system"))
+		setenv("DEBUGINFOD_URLS", di->urls, 1);
+
+	pr_debug("DEBUGINFOD_URLS=%s\n", getenv("DEBUGINFOD_URLS"));
+
+#ifndef HAVE_DEBUGINFOD_SUPPORT
+	if (di->set)
+		pr_warning("WARNING: debuginfod support requested, but perf is not built with it\n");
+#endif
+}
+
+/*
+ * Return a new filename prepended with task's root directory if it's in
+ * a chroot.  Callers should free the returned string.
+ */
+char *filename_with_chroot(int pid, const char *filename)
+{
+	char buf[PATH_MAX];
+	char proc_root[32];
+	char *new_name = NULL;
+	int ret;
+
+	scnprintf(proc_root, sizeof(proc_root), "/proc/%d/root", pid);
+	ret = readlink(proc_root, buf, sizeof(buf) - 1);
+	if (ret <= 0)
+		return NULL;
+
+	/* readlink(2) does not append a null byte to buf */
+	buf[ret] = '\0';
+
+	if (!strcmp(buf, "/"))
+		return NULL;
+
+	if (strstr(buf, "(deleted)"))
+		return NULL;
+
+	if (asprintf(&new_name, "%s/%s", buf, filename) < 0)
+		return NULL;
+
+	return new_name;
+}
+
+/*
+ * Reallocate an array *arr of size *arr_sz so that it is big enough to contain
+ * x elements of size msz, initializing new entries to *init_val or zero if
+ * init_val is NULL
+ */
+int do_realloc_array_as_needed(void **arr, size_t *arr_sz, size_t x, size_t msz, const void *init_val)
+{
+	size_t new_sz = *arr_sz;
+	void *new_arr;
+	size_t i;
+
+	if (!new_sz)
+		new_sz = msz >= 64 ? 1 : roundup(64, msz); /* Start with at least 64 bytes */
+	while (x >= new_sz) {
+		if (check_mul_overflow(new_sz, (size_t)2, &new_sz))
+			return -ENOMEM;
+	}
+	if (new_sz == *arr_sz)
+		return 0;
+	new_arr = calloc(new_sz, msz);
+	if (!new_arr)
+		return -ENOMEM;
+	memcpy(new_arr, *arr, *arr_sz * msz);
+	if (init_val) {
+		for (i = *arr_sz; i < new_sz; i++)
+			memcpy(new_arr + (i * msz), init_val, msz);
+	}
+	*arr = new_arr;
+	*arr_sz = new_sz;
+	return 0;
+}