Clean up maps parsing in libbacktrace.

    map->flags |= PROT_EXEC;

  }

  while (isspace(line[name_pos])) {

    name_pos += 1;

  }

  map->name = line+name_pos;

  if (!map->name.empty() && map->name[map->name.length()-1] == '\n') {

    map->name.erase(map->name.length()-1);

/*

 * Copyright (C) 2013 The Android Open Source Project

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include <ctype.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <limits.h>

#include <pthread.h>

#include <unistd.h>

#include <log/log.h>

#include <sys/time.h>

#include <backtrace/backtrace.h>

#if defined(__APPLE__)

// Mac OS vmmap(1) output:

// __TEXT                 0009f000-000a1000 [    8K     8K] r-x/rwx SM=COW  /Volumes/android/dalvik-dev/out/host/darwin-x86/bin/libcorkscrew_test\n

// 012345678901234567890123456789012345678901234567890123456789

// 0         1         2         3         4         5

static backtrace_map_info_t* parse_vmmap_line(const char* line) {

  unsigned long int start;

  unsigned long int end;

  char permissions[4];

  int name_pos;

  if (sscanf(line, "%*21c %lx-%lx [%*13c] %3c/%*3c SM=%*3c  %n",

             &start, &end, permissions, &name_pos) != 3) {

    return NULL;

  }

  const char* name = line + name_pos;

  size_t name_len = strlen(name);

  backtrace_map_info_t* mi = calloc(1, sizeof(backtrace_map_info_t) + name_len);

  if (mi != NULL) {

    mi->start = start;

    mi->end = end;

    mi->is_readable = permissions[0] == 'r';

    mi->is_writable = permissions[1] == 'w';

    mi->is_executable = permissions[2] == 'x';

    memcpy(mi->name, name, name_len);

    mi->name[name_len - 1] = '\0';

    ALOGV("Parsed map: start=0x%08x, end=0x%08x, "

          "is_readable=%d, is_writable=%d is_executable=%d, name=%s",

          mi->start, mi->end,

          mi->is_readable, mi->is_writable, mi->is_executable, mi->name);

  }

  return mi;

}

backtrace_map_info_t* backtrace_create_map_info_list(pid_t pid) {

  char cmd[1024];

  if (pid < 0) {

    pid = getpid();

  }

  snprintf(cmd, sizeof(cmd), "vmmap -w -resident -submap -allSplitLibs -interleaved %d", pid);

  FILE* fp = popen(cmd, "r");

  if (fp == NULL) {

    return NULL;

  }

  char line[1024];

  backtrace_map_info_t* milist = NULL;

  while (fgets(line, sizeof(line), fp) != NULL) {

    backtrace_map_info_t* mi = parse_vmmap_line(line);

    if (mi != NULL) {

      mi->next = milist;

      milist = mi;

    }

  }

  pclose(fp);

  return milist;

}

#else

// Linux /proc/<pid>/maps lines:

// 6f000000-6f01e000 rwxp 00000000 00:0c 16389419   /system/lib/libcomposer.so\n

// 012345678901234567890123456789012345678901234567890123456789

// 0         1         2         3         4         5

static backtrace_map_info_t* parse_maps_line(const char* line)

{

  unsigned long int start;

  unsigned long int end;

  char permissions[5];

  int name_pos;

  if (sscanf(line, "%lx-%lx %4s %*x %*x:%*x %*d%n", &start, &end,

             permissions, &name_pos) != 3) {

    return NULL;

  }

  while (isspace(line[name_pos])) {

    name_pos += 1;

  }

  const char* name = line + name_pos;

  size_t name_len = strlen(name);

  if (name_len && name[name_len - 1] == '\n') {

    name_len -= 1;

  }

  backtrace_map_info_t* mi = calloc(1, sizeof(backtrace_map_info_t) + name_len + 1);

  if (mi) {

    mi->start = start;

    mi->end = end;

    mi->is_readable = strlen(permissions) == 4 && permissions[0] == 'r';

    mi->is_writable = strlen(permissions) == 4 && permissions[1] == 'w';

    mi->is_executable = strlen(permissions) == 4 && permissions[2] == 'x';

    memcpy(mi->name, name, name_len);

    mi->name[name_len] = '\0';

    ALOGV("Parsed map: start=0x%08x, end=0x%08x, "

          "is_readable=%d, is_writable=%d, is_executable=%d, name=%s",

          mi->start, mi->end,

          mi->is_readable, mi->is_writable, mi->is_executable, mi->name);

  }

  return mi;

}

backtrace_map_info_t* backtrace_create_map_info_list(pid_t tid) {

  char path[PATH_MAX];

  char line[1024];

  FILE* fp;

  backtrace_map_info_t* milist = NULL;

  if (tid < 0) {

    tid = getpid();

  }

  snprintf(path, PATH_MAX, "/proc/%d/maps", tid);

  fp = fopen(path, "r");

  if (fp) {

    while(fgets(line, sizeof(line), fp)) {

      backtrace_map_info_t* mi = parse_maps_line(line);

      if (mi) {

        mi->next = milist;

        milist = mi;

      }

    }

    fclose(fp);

  }

  return milist;

}

#endif

void backtrace_destroy_map_info_list(backtrace_map_info_t* milist) {

  while (milist) {

    backtrace_map_info_t* next = milist->next;

    free(milist);

    milist = next;

  }

}

const backtrace_map_info_t* backtrace_find_map_info(

    const backtrace_map_info_t* milist, uintptr_t addr) {

  const backtrace_map_info_t* mi = milist;

  while (mi && !(addr >= mi->start && addr < mi->end)) {

    mi = mi->next;

  }

  return mi;

}