#include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  
  #include <linux/kernel.h>
  
  #include "util/dso.h"
  #include "util/util.h"
  #include "util/debug.h"
  
  #ifdef HAVE_LIBBFD_SUPPORT
  
  /*
   * Implement addr2line using libbfd.
   */
  #define PACKAGE "perf"
  #include <bfd.h>
  
  struct a2l_data {
  	const char 	*input;
  	unsigned long 	addr;
  
  	bool 		found;
  	const char 	*filename;
  	const char 	*funcname;
  	unsigned 	line;
  
  	bfd 		*abfd;
  	asymbol 	**syms;
  };
  
  static int bfd_error(const char *string)
  {
  	const char *errmsg;
  
  	errmsg = bfd_errmsg(bfd_get_error());
  	fflush(stdout);
  
  	if (string)
  		pr_debug("%s: %s
  ", string, errmsg);
  	else
  		pr_debug("%s
  ", errmsg);
  
  	return -1;
  }
  
  static int slurp_symtab(bfd *abfd, struct a2l_data *a2l)
  {
  	long storage;
  	long symcount;
  	asymbol **syms;
  	bfd_boolean dynamic = FALSE;
  
  	if ((bfd_get_file_flags(abfd) & HAS_SYMS) == 0)
  		return bfd_error(bfd_get_filename(abfd));
  
  	storage = bfd_get_symtab_upper_bound(abfd);
  	if (storage == 0L) {
  		storage = bfd_get_dynamic_symtab_upper_bound(abfd);
  		dynamic = TRUE;
  	}
  	if (storage < 0L)
  		return bfd_error(bfd_get_filename(abfd));
  
  	syms = malloc(storage);
  	if (dynamic)
  		symcount = bfd_canonicalize_dynamic_symtab(abfd, syms);
  	else
  		symcount = bfd_canonicalize_symtab(abfd, syms);
  
  	if (symcount < 0) {
  		free(syms);
  		return bfd_error(bfd_get_filename(abfd));
  	}
  
  	a2l->syms = syms;
  	return 0;
  }
  
  static void find_address_in_section(bfd *abfd, asection *section, void *data)
  {
  	bfd_vma pc, vma;
  	bfd_size_type size;
  	struct a2l_data *a2l = data;
  
  	if (a2l->found)
  		return;
  
  	if ((bfd_get_section_flags(abfd, section) & SEC_ALLOC) == 0)
  		return;
  
  	pc = a2l->addr;
  	vma = bfd_get_section_vma(abfd, section);
  	size = bfd_get_section_size(section);
  
  	if (pc < vma || pc >= vma + size)
  		return;
  
  	a2l->found = bfd_find_nearest_line(abfd, section, a2l->syms, pc - vma,
  					   &a2l->filename, &a2l->funcname,
  					   &a2l->line);
  }
  
  static struct a2l_data *addr2line_init(const char *path)
  {
  	bfd *abfd;
  	struct a2l_data *a2l = NULL;
  
  	abfd = bfd_openr(path, NULL);
  	if (abfd == NULL)
  		return NULL;
  
  	if (!bfd_check_format(abfd, bfd_object))
  		goto out;
  
  	a2l = zalloc(sizeof(*a2l));
  	if (a2l == NULL)
  		goto out;
  
  	a2l->abfd = abfd;
  	a2l->input = strdup(path);
  	if (a2l->input == NULL)
  		goto out;
  
  	if (slurp_symtab(abfd, a2l))
  		goto out;
  
  	return a2l;
  
  out:
  	if (a2l) {
  		zfree((char **)&a2l->input);
  		free(a2l);
  	}
  	bfd_close(abfd);
  	return NULL;
  }
  
  static void addr2line_cleanup(struct a2l_data *a2l)
  {
  	if (a2l->abfd)
  		bfd_close(a2l->abfd);
  	zfree((char **)&a2l->input);
  	zfree(&a2l->syms);
  	free(a2l);
  }
  
  static int addr2line(const char *dso_name, unsigned long addr,
  		     char **file, unsigned int *line, struct dso *dso)
  {
  	int ret = 0;
  	struct a2l_data *a2l = dso->a2l;
  
  	if (!a2l) {
  		dso->a2l = addr2line_init(dso_name);
  		a2l = dso->a2l;
  	}
  
  	if (a2l == NULL) {
  		pr_warning("addr2line_init failed for %s
  ", dso_name);
  		return 0;
  	}
  
  	a2l->addr = addr;
  	a2l->found = false;
  
  	bfd_map_over_sections(a2l->abfd, find_address_in_section, a2l);
  
  	if (a2l->found && a2l->filename) {
  		*file = strdup(a2l->filename);
  		*line = a2l->line;
  
  		if (*file)
  			ret = 1;
  	}
  
  	return ret;
  }
  
  void dso__free_a2l(struct dso *dso)
  {
  	struct a2l_data *a2l = dso->a2l;
  
  	if (!a2l)
  		return;
  
  	addr2line_cleanup(a2l);
  
  	dso->a2l = NULL;
  }
  
  #else /* HAVE_LIBBFD_SUPPORT */
  
  static int addr2line(const char *dso_name, unsigned long addr,
  		     char **file, unsigned int *line_nr,
  		     struct dso *dso __maybe_unused)
  {
  	FILE *fp;
  	char cmd[PATH_MAX];
  	char *filename = NULL;
  	size_t len;
  	char *sep;
  	int ret = 0;
  
  	scnprintf(cmd, sizeof(cmd), "addr2line -e %s %016"PRIx64,
  		  dso_name, addr);
  
  	fp = popen(cmd, "r");
  	if (fp == NULL) {
  		pr_warning("popen failed for %s
  ", dso_name);
  		return 0;
  	}
  
  	if (getline(&filename, &len, fp) < 0 || !len) {
  		pr_warning("addr2line has no output for %s
  ", dso_name);
  		goto out;
  	}
  
  	sep = strchr(filename, '
  ');
  	if (sep)
  		*sep = '\0';
  
  	if (!strcmp(filename, "??:0")) {
  		pr_debug("no debugging info in %s
  ", dso_name);
  		free(filename);
  		goto out;
  	}
  
  	sep = strchr(filename, ':');
  	if (sep) {
  		*sep++ = '\0';
  		*file = filename;
  		*line_nr = strtoul(sep, NULL, 0);
  		ret = 1;
  	}
  out:
  	pclose(fp);
  	return ret;
  }
  
  void dso__free_a2l(struct dso *dso __maybe_unused)
  {
  }
  
  #endif /* HAVE_LIBBFD_SUPPORT */
  
  /*
   * Number of addr2line failures (without success) before disabling it for that
   * dso.
   */
  #define A2L_FAIL_LIMIT 123
  
  char *get_srcline(struct dso *dso, unsigned long addr)
  {
  	char *file = NULL;
  	unsigned line = 0;
  	char *srcline;
  	const char *dso_name;
  
  	if (!dso->has_srcline)
  		return SRCLINE_UNKNOWN;
  
  	if (dso->symsrc_filename)
  		dso_name = dso->symsrc_filename;
  	else
  		dso_name = dso->long_name;
  
  	if (dso_name[0] == '[')
  		goto out;
  
  	if (!strncmp(dso_name, "/tmp/perf-", 10))
  		goto out;
  
  	if (!addr2line(dso_name, addr, &file, &line, dso))
  		goto out;
  
  	if (asprintf(&srcline, "%s:%u", file, line) < 0) {
  		free(file);
  		goto out;
  	}
  
  	dso->a2l_fails = 0;
  
  	free(file);
  	return srcline;
  
  out:
  	if (dso->a2l_fails && ++dso->a2l_fails > A2L_FAIL_LIMIT) {
  		dso->has_srcline = 0;
  		dso__free_a2l(dso);
  	}
  	return SRCLINE_UNKNOWN;
  }
  
  void free_srcline(char *srcline)
  {
  	if (srcline && strcmp(srcline, SRCLINE_UNKNOWN) != 0)
  		free(srcline);
  }