| #!/bin/bash |
| # Copyright 2012 The Chromium Authors |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| # |
| # Saves the gdb index for a given binary and its shared library dependencies. |
| # |
| # This will run gdb index in parallel on a number of binaries using SIGUSR1 |
| # as the communication mechanism to simulate a semaphore. Because of the |
| # nature of this technique, using "set -e" is very difficult. The SIGUSR1 |
| # terminates a "wait" with an error which we need to interpret. |
| # |
| # When modifying this code, most of the real logic is in the index_one_file |
| # function. The rest is cleanup + sempahore plumbing. |
| |
| function usage_exit{ |
| echo"Usage: $0 [-f] [-r] [-n] <paths-to-binaries>..." |
| echo" -f forces replacement of an existing index." |
| echo" -r removes the index section." |
| echo" -n don't extract the dependencies of each binary with lld." |
| echo" e.g., $0 -n out/Debug/lib.unstripped/lib*" |
| echo |
| echo" Set TOOLCHAIN_PREFIX to use a non-default set of binutils." |
| exit1 |
| } |
| |
| # Cleanup temp directory and ensure all child jobs are dead-dead. |
| function on_exit{ |
| trap"" EXIT USR1# Avoid reentrancy. |
| |
| local jobs=$(jobs-p) |
| if[-n"$jobs"];then |
| echo-n"Killing outstanding index jobs..." |
| kill-KILL $(jobs-p) |
| wait |
| echo"done" |
| fi |
| |
| if[-d"$directory"];then |
| echo-n"Removing temp directory $directory..." |
| rm-rf"$directory" |
| echodone |
| fi |
| } |
| |
| # Add index to one binary. |
| function index_one_file{ |
| local file=$1 |
| local basename=$(basename"$file") |
| local should_index_this_file="${should_index}" |
| |
| local readelf_out=$(${TOOLCHAIN_PREFIX}readelf-S"$file") |
| if[[ $readelf_out=~"gdb_index"]];then |
| if $remove_index;then |
| ${TOOLCHAIN_PREFIX}objcopy--remove-section.gdb_index"$file" |
| echo"Removed index from $basename." |
| else |
| echo"Skipped $basename -- already contains index." |
| should_index_this_file=false |
| fi |
| fi |
| |
| if $should_index_this_file;then |
| local start=$(date+"%s%N") |
| echo"Adding index to $basename..." |
| |
| ${TOOLCHAIN_PREFIX}gdb-batch"$file"-ex"save gdb-index $directory" \ |
| -ex"quit" |
| local index_file="$directory/$basename.gdb-index" |
| if[-f"$index_file"];then |
| ${TOOLCHAIN_PREFIX}objcopy--add-section.gdb_index="$index_file" \ |
| --set-section-flags.gdb_index=readonly"$file""$file" |
| local finish=$(date+"%s%N") |
| local elapsed=$(((finish- start)/1000000)) |
| echo" ...$basename indexed. [${elapsed}ms]" |
| else |
| echo" ...$basename unindexable." |
| fi |
| fi |
| } |
| |
| # Functions that when combined, concurrently index all files in FILES_TO_INDEX |
| # array. The global FILES_TO_INDEX is declared in the main body of the script. |
| function async_index{ |
| # Start a background subshell to run the index command. |
| { |
| index_one_file $1 |
| kill-SIGUSR1 $$# $$ resolves to the parent script. |
| exit129# See comment above wait loop at bottom. |
| }& |
| } |
| |
| cur_file_num=0 |
| function index_next{ |
| if((cur_file_num>= ${#files_to_index[@]}));then |
| return |
| fi |
| |
| async_index"${files_to_index[cur_file_num]}" |
| ((cur_file_num+=1))|| true |
| } |
| |
| ######## |
| ### Main body of the script. |
| |
| remove_index=false |
| should_index=true |
| should_index_deps=true |
| files_to_index=() |
| while(($# > 0)); do |
| case"$1"in |
| -h) |
| usage_exit |
| ;; |
| -f) |
| remove_index=true |
| ;; |
| -r) |
| remove_index=true |
| should_index=false |
| ;; |
| -n) |
| should_index_deps=false |
| ;; |
| -*) |
| echo"Invalid option: $1">&2 |
| usage_exit |
| ;; |
| *) |
| if[[!-f"$1"]];then |
| echo"Path $1 does not exist." |
| exit1 |
| fi |
| files_to_index+=("$1") |
| ;; |
| esac |
| shift |
| done |
| |
| if((${#files_to_index[@]}==0));then |
| usage_exit |
| fi |
| |
| dependencies=() |
| if $should_index_deps;then |
| for filein"${files_to_index[@]}";do |
| # Append the shared library dependencies of this file that |
| # have the same dirname. The dirname is a signal that these |
| # shared libraries were part of the same build as the binary. |
| dependencies+=( \ |
| $(ldd"$file"2>/dev/null \ |
| | grep $(dirname"$file") \ |
| | sed"s/.*[ \t]\(.*\) (.*/\1/") \ |
| ) |
| done |
| fi |
| files_to_index+=("${dependencies[@]}") |
| |
| # Ensure we cleanup on on exit. |
| trap on_exit EXIT INT |
| |
| # We're good to go! Create temp directory for index files. |
| directory=$(mktemp-d) |
| echo"Made temp directory $directory." |
| |
| # Start concurrent indexing. |
| trap index_next USR1 |
| |
| # 4 is an arbitrary default. When changing, remember we are likely IO bound |
| # so basing this off the number of cores is not sensible. |
| index_tasks=${INDEX_TASKS:-4} |
| for((i=0; i< index_tasks; i++));do |
| index_next |
| done |
| |
| # Do a wait loop. Bash waits that terminate due a trap have an exit |
| # code > 128. We also ensure that our subshell's "normal" exit occurs with |
| # an exit code > 128. This allows us to do consider a > 128 exit code as |
| # an indication that the loop should continue. Unfortunately, it also means |
| # we cannot use set -e since technically the "wait" is failing. |
| wait |
| while(($?>128));do |
| wait |
| done |
