/*
   * build-id.c
   *
   * build-id support
   *
   * Copyright (C) 2009, 2010 Red Hat Inc.
   * Copyright (C) 2009, 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
   */

  #include "util.h"
  #include <stdio.h>

  #include "build-id.h"
  #include "event.h"
  #include "symbol.h"
  #include <linux/kernel.h>

  #include "debug.h"

  #include "session.h"

  #include "tool.h"

  #include "header.h"
  #include "vdso.h"

  
  static bool no_buildid_cache;

  int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
  			   union perf_event *event,

  			   struct perf_sample *sample,

  			   struct perf_evsel *evsel __maybe_unused,
  			   struct machine *machine)

  {
  	struct addr_location al;
  	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;

  	struct thread *thread = machine__findnew_thread(machine, sample->pid,

  							sample->tid);

  
  	if (thread == NULL) {
  		pr_err("problem processing %d event, skipping it.
  ",
  			event->header.type);
  		return -1;
  	}

  	thread__find_addr_map(thread, cpumode, MAP__FUNCTION, sample->ip, &al);

  
  	if (al.map != NULL)
  		al.map->dso->hit = 1;
  
  	return 0;
  }

  static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,

  				       union perf_event *event,

  				       struct perf_sample *sample
  				       __maybe_unused,

  				       struct machine *machine)

  {

  	struct thread *thread = machine__findnew_thread(machine,
  							event->fork.pid,
  							event->fork.tid);

  	dump_printf("(%d:%d):(%d:%d)
  ", event->fork.pid, event->fork.tid,
  		    event->fork.ppid, event->fork.ptid);

  
  	if (thread) {

  		rb_erase(&thread->rb_node, &machine->threads);
  		machine->last_match = NULL;

  		thread__delete(thread);
  	}
  
  	return 0;
  }

  struct perf_tool build_id__mark_dso_hit_ops = {

  	.sample	= build_id__mark_dso_hit,

  	.mmap	= perf_event__process_mmap,

  	.mmap2	= perf_event__process_mmap2,

  	.fork	= perf_event__process_fork,

  	.exit	= perf_event__exit_del_thread,

  	.attr		 = perf_event__process_attr,
  	.build_id	 = perf_event__process_build_id,

  };

  int build_id__sprintf(const u8 *build_id, int len, char *bf)
  {
  	char *bid = bf;
  	const u8 *raw = build_id;
  	int i;
  
  	for (i = 0; i < len; ++i) {
  		sprintf(bid, "%02x", *raw);
  		++raw;
  		bid += 2;
  	}
  
  	return raw - build_id;
  }

  char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size)

  {
  	char build_id_hex[BUILD_ID_SIZE * 2 + 1];

  	if (!dso->has_build_id)

  		return NULL;

  	build_id__sprintf(dso->build_id, sizeof(dso->build_id), build_id_hex);

  	if (bf == NULL) {

  		if (asprintf(&bf, "%s/.build-id/%.2s/%s", buildid_dir,
  			     build_id_hex, build_id_hex + 2) < 0)

  			return NULL;
  	} else

  		snprintf(bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
  			 build_id_hex, build_id_hex + 2);

  	return bf;
  }

  
  #define dsos__for_each_with_build_id(pos, head)	\
  	list_for_each_entry(pos, head, node)	\
  		if (!pos->has_build_id)		\
  			continue;		\
  		else
  
  static int write_buildid(const char *name, size_t name_len, u8 *build_id,
  			 pid_t pid, u16 misc, int fd)
  {
  	int err;
  	struct build_id_event b;
  	size_t len;
  
  	len = name_len + 1;
  	len = PERF_ALIGN(len, NAME_ALIGN);
  
  	memset(&b, 0, sizeof(b));
  	memcpy(&b.build_id, build_id, BUILD_ID_SIZE);
  	b.pid = pid;
  	b.header.misc = misc;
  	b.header.size = sizeof(b) + len;
  
  	err = writen(fd, &b, sizeof(b));
  	if (err < 0)
  		return err;
  
  	return write_padded(fd, name, name_len + 1, len);
  }
  
  static int __dsos__write_buildid_table(struct list_head *head,
  				       struct machine *machine,
  				       pid_t pid, u16 misc, int fd)
  {
  	char nm[PATH_MAX];
  	struct dso *pos;
  
  	dsos__for_each_with_build_id(pos, head) {
  		int err;
  		const char *name;
  		size_t name_len;
  
  		if (!pos->hit)
  			continue;
  
  		if (dso__is_vdso(pos)) {
  			name = pos->short_name;
  			name_len = pos->short_name_len + 1;
  		} else if (dso__is_kcore(pos)) {
  			machine__mmap_name(machine, nm, sizeof(nm));
  			name = nm;
  			name_len = strlen(nm) + 1;
  		} else {
  			name = pos->long_name;
  			name_len = pos->long_name_len + 1;
  		}
  
  		err = write_buildid(name, name_len, pos->build_id,
  				    pid, misc, fd);
  		if (err)
  			return err;
  	}
  
  	return 0;
  }
  
  static int machine__write_buildid_table(struct machine *machine, int fd)
  {
  	int err;
  	u16 kmisc = PERF_RECORD_MISC_KERNEL,
  	    umisc = PERF_RECORD_MISC_USER;
  
  	if (!machine__is_host(machine)) {
  		kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
  		umisc = PERF_RECORD_MISC_GUEST_USER;
  	}
  
  	err = __dsos__write_buildid_table(&machine->kernel_dsos.head, machine,
  					  machine->pid, kmisc, fd);
  	if (err == 0)
  		err = __dsos__write_buildid_table(&machine->user_dsos.head,
  						  machine, machine->pid, umisc,
  						  fd);
  	return err;
  }
  
  int perf_session__write_buildid_table(struct perf_session *session, int fd)
  {
  	struct rb_node *nd;
  	int err = machine__write_buildid_table(&session->machines.host, fd);
  
  	if (err)
  		return err;
  
  	for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
  		struct machine *pos = rb_entry(nd, struct machine, rb_node);
  		err = machine__write_buildid_table(pos, fd);
  		if (err)
  			break;
  	}
  	return err;
  }
  
  static int __dsos__hit_all(struct list_head *head)
  {
  	struct dso *pos;
  
  	list_for_each_entry(pos, head, node)
  		pos->hit = true;
  
  	return 0;
  }
  
  static int machine__hit_all_dsos(struct machine *machine)
  {
  	int err;
  
  	err = __dsos__hit_all(&machine->kernel_dsos.head);
  	if (err)
  		return err;
  
  	return __dsos__hit_all(&machine->user_dsos.head);
  }
  
  int dsos__hit_all(struct perf_session *session)
  {
  	struct rb_node *nd;
  	int err;
  
  	err = machine__hit_all_dsos(&session->machines.host);
  	if (err)
  		return err;
  
  	for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
  		struct machine *pos = rb_entry(nd, struct machine, rb_node);
  
  		err = machine__hit_all_dsos(pos);
  		if (err)
  			return err;
  	}
  
  	return 0;
  }

  void disable_buildid_cache(void)
  {
  	no_buildid_cache = true;
  }

  int build_id_cache__add_s(const char *sbuild_id, const char *debugdir,
  			  const char *name, bool is_kallsyms, bool is_vdso)
  {
  	const size_t size = PATH_MAX;
  	char *realname, *filename = zalloc(size),
  	     *linkname = zalloc(size), *targetname;
  	int len, err = -1;
  	bool slash = is_kallsyms || is_vdso;
  
  	if (is_kallsyms) {
  		if (symbol_conf.kptr_restrict) {
  			pr_debug("Not caching a kptr_restrict'ed /proc/kallsyms
  ");
  			err = 0;
  			goto out_free;
  		}
  		realname = (char *) name;
  	} else
  		realname = realpath(name, NULL);
  
  	if (realname == NULL || filename == NULL || linkname == NULL)
  		goto out_free;
  
  	len = scnprintf(filename, size, "%s%s%s",
  		       debugdir, slash ? "/" : "",
  		       is_vdso ? DSO__NAME_VDSO : realname);
  	if (mkdir_p(filename, 0755))
  		goto out_free;
  
  	snprintf(filename + len, size - len, "/%s", sbuild_id);
  
  	if (access(filename, F_OK)) {
  		if (is_kallsyms) {
  			 if (copyfile("/proc/kallsyms", filename))
  				goto out_free;
  		} else if (link(realname, filename) && copyfile(name, filename))
  			goto out_free;
  	}
  
  	len = scnprintf(linkname, size, "%s/.build-id/%.2s",
  		       debugdir, sbuild_id);
  
  	if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
  		goto out_free;
  
  	snprintf(linkname + len, size - len, "/%s", sbuild_id + 2);
  	targetname = filename + strlen(debugdir) - 5;
  	memcpy(targetname, "../..", 5);
  
  	if (symlink(targetname, linkname) == 0)
  		err = 0;
  out_free:
  	if (!is_kallsyms)
  		free(realname);
  	free(filename);
  	free(linkname);
  	return err;
  }
  
  static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
  				 const char *name, const char *debugdir,
  				 bool is_kallsyms, bool is_vdso)
  {
  	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
  
  	build_id__sprintf(build_id, build_id_size, sbuild_id);
  
  	return build_id_cache__add_s(sbuild_id, debugdir, name,
  				     is_kallsyms, is_vdso);
  }
  
  int build_id_cache__remove_s(const char *sbuild_id, const char *debugdir)
  {
  	const size_t size = PATH_MAX;
  	char *filename = zalloc(size),
  	     *linkname = zalloc(size);
  	int err = -1;
  
  	if (filename == NULL || linkname == NULL)
  		goto out_free;
  
  	snprintf(linkname, size, "%s/.build-id/%.2s/%s",
  		 debugdir, sbuild_id, sbuild_id + 2);
  
  	if (access(linkname, F_OK))
  		goto out_free;
  
  	if (readlink(linkname, filename, size - 1) < 0)
  		goto out_free;
  
  	if (unlink(linkname))
  		goto out_free;
  
  	/*
  	 * Since the link is relative, we must make it absolute:
  	 */
  	snprintf(linkname, size, "%s/.build-id/%.2s/%s",
  		 debugdir, sbuild_id, filename);
  
  	if (unlink(linkname))
  		goto out_free;
  
  	err = 0;
  out_free:
  	free(filename);
  	free(linkname);
  	return err;
  }
  
  static int dso__cache_build_id(struct dso *dso, struct machine *machine,
  			       const char *debugdir)
  {
  	bool is_kallsyms = dso->kernel && dso->long_name[0] != '/';
  	bool is_vdso = dso__is_vdso(dso);
  	const char *name = dso->long_name;
  	char nm[PATH_MAX];
  
  	if (dso__is_kcore(dso)) {
  		is_kallsyms = true;
  		machine__mmap_name(machine, nm, sizeof(nm));
  		name = nm;
  	}
  	return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id), name,
  				     debugdir, is_kallsyms, is_vdso);
  }
  
  static int __dsos__cache_build_ids(struct list_head *head,
  				   struct machine *machine, const char *debugdir)
  {
  	struct dso *pos;
  	int err = 0;
  
  	dsos__for_each_with_build_id(pos, head)
  		if (dso__cache_build_id(pos, machine, debugdir))
  			err = -1;
  
  	return err;
  }
  
  static int machine__cache_build_ids(struct machine *machine, const char *debugdir)
  {
  	int ret = __dsos__cache_build_ids(&machine->kernel_dsos.head, machine,
  					  debugdir);
  	ret |= __dsos__cache_build_ids(&machine->user_dsos.head, machine,
  				       debugdir);
  	return ret;
  }
  
  int perf_session__cache_build_ids(struct perf_session *session)
  {
  	struct rb_node *nd;
  	int ret;

  	if (no_buildid_cache)
  		return 0;

  	if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)

  		return -1;

  	ret = machine__cache_build_ids(&session->machines.host, buildid_dir);

  
  	for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
  		struct machine *pos = rb_entry(nd, struct machine, rb_node);

  		ret |= machine__cache_build_ids(pos, buildid_dir);

  	}
  	return ret ? -1 : 0;
  }
  
  static bool machine__read_build_ids(struct machine *machine, bool with_hits)
  {
  	bool ret;
  
  	ret  = __dsos__read_build_ids(&machine->kernel_dsos.head, with_hits);
  	ret |= __dsos__read_build_ids(&machine->user_dsos.head, with_hits);
  	return ret;
  }
  
  bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
  {
  	struct rb_node *nd;
  	bool ret = machine__read_build_ids(&session->machines.host, with_hits);
  
  	for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
  		struct machine *pos = rb_entry(nd, struct machine, rb_node);
  		ret |= machine__read_build_ids(pos, with_hits);
  	}
  
  	return ret;
  }