text: // SPDX-License-Identifier: GPL-2.0
  #include <inttypes.h>
  #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"
  #include "util/callchain.h"
  #include "srcline.h"
  #include "string2.h"
  #include "symbol.h"
  
  bool srcline_full_filename;
  
  static const char *dso__name(struct dso *dso)
  {
  	const char *dso_name;
  
  	if (dso->symsrc_filename)
  		dso_name = dso->symsrc_filename;
  	else
  		dso_name = dso->long_name;
  
  	if (dso_name[0] == '[')
  		return NULL;
  
  	if (!strncmp(dso_name, "/tmp/perf-", 10))
  		return NULL;
  
  	return dso_name;
  }
  
  static int inline_list__append(struct symbol *symbol, char *srcline,
  			       struct inline_node *node)
  {
  	struct inline_list *ilist;
  
  	ilist = zalloc(sizeof(*ilist));
  	if (ilist == NULL)
  		return -1;
  
  	ilist->symbol = symbol;
  	ilist->srcline = srcline;
  
  	if (callchain_param.order == ORDER_CALLEE)
  		list_add_tail(&ilist->list, &node->val);
  	else
  		list_add(&ilist->list, &node->val);
  
  	return 0;
  }
  
  /* basename version that takes a const input string */
  static const char *gnu_basename(const char *path)
  {
  	const char *base = strrchr(path, '/');
  
  	return base ? base + 1 : path;
  }
  
  static char *srcline_from_fileline(const char *file, unsigned int line)
  {
  	char *srcline;
  
  	if (!file)
  		return NULL;
  
  	if (!srcline_full_filename)
  		file = gnu_basename(file);
  
  	if (asprintf(&srcline, "%s:%u", file, line) < 0)
  		return NULL;
  
  	return srcline;
  }
  
  static struct symbol *new_inline_sym(struct dso *dso,
  				     struct symbol *base_sym,
  				     const char *funcname)
  {
  	struct symbol *inline_sym;
  	char *demangled = NULL;
  
  	if (dso) {
  		demangled = dso__demangle_sym(dso, 0, funcname);
  		if (demangled)
  			funcname = demangled;
  	}
  
  	if (base_sym && strcmp(funcname, base_sym->name) == 0) {
  		/* reuse the real, existing symbol */
  		inline_sym = base_sym;
  		/* ensure that we don't alias an inlined symbol, which could
  		 * lead to double frees in inline_node__delete
  		 */
  		assert(!base_sym->inlined);
  	} else {
  		/* create a fake symbol for the inline frame */
  		inline_sym = symbol__new(base_sym ? base_sym->start : 0,
  					 base_sym ? base_sym->end : 0,
  					 base_sym ? base_sym->binding : 0,
  					 funcname);
  		if (inline_sym)
  			inline_sym->inlined = 1;
  	}
  
  	free(demangled);
  
  	return inline_sym;
  }
  
  #ifdef HAVE_LIBBFD_SUPPORT
  
  /*
   * Implement addr2line using libbfd.
   */
  #define PACKAGE "perf"
  #include <bfd.h>
  
  struct a2l_data {
  	const char 	*input;
  	u64	 	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\n", string, errmsg);
  	else
  		pr_debug("%s\n", 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);
  
  	if (a2l->filename && !strlen(a2l->filename))
  		a2l->filename = NULL;
  }
  
  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);
  }
  
  #define MAX_INLINE_NEST 1024
  
  static int inline_list__append_dso_a2l(struct dso *dso,
  				       struct inline_node *node,
  				       struct symbol *sym)
  {
  	struct a2l_data *a2l = dso->a2l;
  	struct symbol *inline_sym = new_inline_sym(dso, sym, a2l->funcname);
  	char *srcline = NULL;
  
  	if (a2l->filename)
  		srcline = srcline_from_fileline(a2l->filename, a2l->line);
  
  	return inline_list__append(inline_sym, srcline, node);
  }
  
  static int addr2line(const char *dso_name, u64 addr,
  		     char **file, unsigned int *line, struct dso *dso,
  		     bool unwind_inlines, struct inline_node *node,
  		     struct symbol *sym)
  {
  	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\n", dso_name);
  		return 0;
  	}
  
  	a2l->addr = addr;
  	a2l->found = false;
  
  	bfd_map_over_sections(a2l->abfd, find_address_in_section, a2l);
  
  	if (!a2l->found)
  		return 0;
  
  	if (unwind_inlines) {
  		int cnt = 0;
  
  		if (node && inline_list__append_dso_a2l(dso, node, sym))
  			return 0;
  
  		while (bfd_find_inliner_info(a2l->abfd, &a2l->filename,
  					     &a2l->funcname, &a2l->line) &&
  		       cnt++ < MAX_INLINE_NEST) {
  
  			if (a2l->filename && !strlen(a2l->filename))
  				a2l->filename = NULL;
  
  			if (node != NULL) {
  				if (inline_list__append_dso_a2l(dso, node, sym))
  					return 0;
  				// found at least one inline frame
  				ret = 1;
  			}
  		}
  	}
  
  	if (file) {
  		*file = a2l->filename ? strdup(a2l->filename) : NULL;
  		ret = *file ? 1 : 0;
  	}
  
  	if (line)
  		*line = a2l->line;
  
  	return ret;
  }
  
  void dso__free_a2l(struct dso *dso)
  {
  	struct a2l_data *a2l = dso->a2l;
  
  	if (!a2l)
  		return;
  
  	addr2line_cleanup(a2l);
  
  	dso->a2l = NULL;
  }
  
  static struct inline_node *addr2inlines(const char *dso_name, u64 addr,
  					struct dso *dso, struct symbol *sym)
  {
  	struct inline_node *node;
  
  	node = zalloc(sizeof(*node));
  	if (node == NULL) {
  		perror("not enough memory for the inline node");
  		return NULL;
  	}
  
  	INIT_LIST_HEAD(&node->val);
  	node->addr = addr;
  
  	addr2line(dso_name, addr, NULL, NULL, dso, true, node, sym);
  	return node;
  }
  
  #else /* HAVE_LIBBFD_SUPPORT */
  
  static int filename_split(char *filename, unsigned int *line_nr)
  {
  	char *sep;
  
  	sep = strchr(filename, '\n');
  	if (sep)
  		*sep = '\0';
  
  	if (!strcmp(filename, "??:0"))
  		return 0;
  
  	sep = strchr(filename, ':');
  	if (sep) {
  		*sep++ = '\0';
  		*line_nr = strtoul(sep, NULL, 0);
  		return 1;
  	}
  
  	return 0;
  }
  
  static int addr2line(const char *dso_name, u64 addr,
  		     char **file, unsigned int *line_nr,
  		     struct dso *dso __maybe_unused,
  		     bool unwind_inlines __maybe_unused,
  		     struct inline_node *node __maybe_unused,
  		     struct symbol *sym __maybe_unused)
  {
  	FILE *fp;
  	char cmd[PATH_MAX];
  	char *filename = NULL;
  	size_t len;
  	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\n", dso_name);
  		return 0;
  	}
  
  	if (getline(&filename, &len, fp) < 0 || !len) {
  		pr_warning("addr2line has no output for %s\n", dso_name);
  		goto out;
  	}
  
  	ret = filename_split(filename, line_nr);
  	if (ret != 1) {
  		free(filename);
  		goto out;
  	}
  
  	*file = filename;
  
  out:
  	pclose(fp);
  	return ret;
  }
  
  void dso__free_a2l(struct dso *dso __maybe_unused)
  {
  }
  
  static struct inline_node *addr2inlines(const char *dso_name, u64 addr,
  					struct dso *dso __maybe_unused,
  					struct symbol *sym)
  {
  	FILE *fp;
  	char cmd[PATH_MAX];
  	struct inline_node *node;
  	char *filename = NULL;
  	char *funcname = NULL;
  	size_t filelen, funclen;
  	unsigned int line_nr = 0;
  
  	scnprintf(cmd, sizeof(cmd), "addr2line -e %s -i -f %016"PRIx64,
  		  dso_name, addr);
  
  	fp = popen(cmd, "r");
  	if (fp == NULL) {
  		pr_err("popen failed for %s\n", dso_name);
  		return NULL;
  	}
  
  	node = zalloc(sizeof(*node));
  	if (node == NULL) {
  		perror("not enough memory for the inline node");
  		goto out;
  	}
  
  	INIT_LIST_HEAD(&node->val);
  	node->addr = addr;
  
  	/* addr2line -f generates two lines for each inlined functions */
  	while (getline(&funcname, &funclen, fp) != -1) {
  		char *srcline;
  		struct symbol *inline_sym;
  
  		rtrim(funcname);
  
  		if (getline(&filename, &filelen, fp) == -1)
  			goto out;
  
  		if (filename_split(filename, &line_nr) != 1)
  			goto out;
  
  		srcline = srcline_from_fileline(filename, line_nr);
  		inline_sym = new_inline_sym(dso, sym, funcname);
  
  		if (inline_list__append(inline_sym, srcline, node) != 0) {
  			free(srcline);
  			if (inline_sym && inline_sym->inlined)
  				symbol__delete(inline_sym);
  			goto out;
  		}
  	}
  
  out:
  	pclose(fp);
  	free(filename);
  	free(funcname);
  
  	return node;
  }
  
  #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, u64 addr, struct symbol *sym,
  		  bool show_sym, bool show_addr, bool unwind_inlines)
  {
  	char *file = NULL;
  	unsigned line = 0;
  	char *srcline;
  	const char *dso_name;
  
  	if (!dso->has_srcline)
  		goto out;
  
  	dso_name = dso__name(dso);
  	if (dso_name == NULL)
  		goto out;
  
  	if (!addr2line(dso_name, addr, &file, &line, dso,
  		       unwind_inlines, NULL, sym))
  		goto out;
  
  	srcline = srcline_from_fileline(file, line);
  	free(file);
  
  	if (!srcline)
  		goto out;
  
  	dso->a2l_fails = 0;
  
  	return srcline;
  
  out:
  	if (dso->a2l_fails && ++dso->a2l_fails > A2L_FAIL_LIMIT) {
  		dso->has_srcline = 0;
  		dso__free_a2l(dso);
  	}
  
  	if (!show_addr)
  		return (show_sym && sym) ?
  			    strndup(sym->name, sym->namelen) : NULL;
  
  	if (sym) {
  		if (asprintf(&srcline, "%s+%" PRIu64, show_sym ? sym->name : "",
  					addr - sym->start) < 0)
  			return SRCLINE_UNKNOWN;
  	} else if (asprintf(&srcline, "%s[%" PRIx64 "]", dso->short_name, addr) < 0)
  		return SRCLINE_UNKNOWN;
  	return srcline;
  }
  
  void free_srcline(char *srcline)
  {
  	if (srcline && strcmp(srcline, SRCLINE_UNKNOWN) != 0)
  		free(srcline);
  }
  
  char *get_srcline(struct dso *dso, u64 addr, struct symbol *sym,
  		  bool show_sym, bool show_addr)
  {
  	return __get_srcline(dso, addr, sym, show_sym, show_addr, false);
  }
  
  struct srcline_node {
  	u64			addr;
  	char			*srcline;
  	struct rb_node		rb_node;
  };
  
  void srcline__tree_insert(struct rb_root *tree, u64 addr, char *srcline)
  {
  	struct rb_node **p = &tree->rb_node;
  	struct rb_node *parent = NULL;
  	struct srcline_node *i, *node;
  
  	node = zalloc(sizeof(struct srcline_node));
  	if (!node) {
  		perror("not enough memory for the srcline node");
  		return;
  	}
  
  	node->addr = addr;
  	node->srcline = srcline;
  
  	while (*p != NULL) {
  		parent = *p;
  		i = rb_entry(parent, struct srcline_node, rb_node);
  		if (addr < i->addr)
  			p = &(*p)->rb_left;
  		else
  			p = &(*p)->rb_right;
  	}
  	rb_link_node(&node->rb_node, parent, p);
  	rb_insert_color(&node->rb_node, tree);
  }
  
  char *srcline__tree_find(struct rb_root *tree, u64 addr)
  {
  	struct rb_node *n = tree->rb_node;
  
  	while (n) {
  		struct srcline_node *i = rb_entry(n, struct srcline_node,
  						  rb_node);
  
  		if (addr < i->addr)
  			n = n->rb_left;
  		else if (addr > i->addr)
  			n = n->rb_right;
  		else
  			return i->srcline;
  	}
  
  	return NULL;
  }
  
  void srcline__tree_delete(struct rb_root *tree)
  {
  	struct srcline_node *pos;
  	struct rb_node *next = rb_first(tree);
  
  	while (next) {
  		pos = rb_entry(next, struct srcline_node, rb_node);
  		next = rb_next(&pos->rb_node);
  		rb_erase(&pos->rb_node, tree);
  		free_srcline(pos->srcline);
  		zfree(&pos);
  	}
  }
  
  struct inline_node *dso__parse_addr_inlines(struct dso *dso, u64 addr,
  					    struct symbol *sym)
  {
  	const char *dso_name;
  
  	dso_name = dso__name(dso);
  	if (dso_name == NULL)
  		return NULL;
  
  	return addr2inlines(dso_name, addr, dso, sym);
  }
  
  void inline_node__delete(struct inline_node *node)
  {
  	struct inline_list *ilist, *tmp;
  
  	list_for_each_entry_safe(ilist, tmp, &node->val, list) {
  		list_del_init(&ilist->list);
  		free_srcline(ilist->srcline);
  		/* only the inlined symbols are owned by the list */
  		if (ilist->symbol && ilist->symbol->inlined)
  			symbol__delete(ilist->symbol);
  		free(ilist);
  	}
  
  	free(node);
  }
  
  void inlines__tree_insert(struct rb_root *tree, struct inline_node *inlines)
  {
  	struct rb_node **p = &tree->rb_node;
  	struct rb_node *parent = NULL;
  	const u64 addr = inlines->addr;
  	struct inline_node *i;
  
  	while (*p != NULL) {
  		parent = *p;
  		i = rb_entry(parent, struct inline_node, rb_node);
  		if (addr < i->addr)
  			p = &(*p)->rb_left;
  		else
  			p = &(*p)->rb_right;
  	}
  	rb_link_node(&inlines->rb_node, parent, p);
  	rb_insert_color(&inlines->rb_node, tree);
  }
  
  struct inline_node *inlines__tree_find(struct rb_root *tree, u64 addr)
  {
  	struct rb_node *n = tree->rb_node;
  
  	while (n) {
  		struct inline_node *i = rb_entry(n, struct inline_node,
  						 rb_node);
  
  		if (addr < i->addr)
  			n = n->rb_left;
  		else if (addr > i->addr)
  			n = n->rb_right;
  		else
  			return i;
  	}
  
  	return NULL;
  }
  
  void inlines__tree_delete(struct rb_root *tree)
  {
  	struct inline_node *pos;
  	struct rb_node *next = rb_first(tree);
  
  	while (next) {
  		pos = rb_entry(next, struct inline_node, rb_node);
  		next = rb_next(&pos->rb_node);
  		rb_erase(&pos->rb_node, tree);
  		inline_node__delete(pos);
  	}
  }
  