From 7be99c5140c40b9fc45b2a8e051d1f7e1598ddbf Mon Sep 17 00:00:00 2001
From: Daniel Nichter <daniel@percona.com>
Date: Thu, 2 Feb 2012 12:04:28 -0700
Subject: [PATCH] Add _which() to alt_cmds.sh and update pt-stalk.

---
 bin/pt-stalk         | 33 +++++++++++++++++++--------------
 lib/bash/alt_cmds.sh |  6 ++++++
 lib/bash/collect.sh  | 32 ++++++++++++++++++--------------
 3 files changed, 43 insertions(+), 28 deletions(-)

diff --git a/bin/pt-stalk b/bin/pt-stalk
index c7a3168b..a7ded134 100755
--- a/bin/pt-stalk
+++ b/bin/pt-stalk
@@ -486,6 +486,10 @@ _lsof() {
    fi
 }
 
+_which() {
+   [ -x /usr/bin/which ] && /usr/bin/which "$1" 2>/dev/null | awk '{print $1}'
+}
+
 # ###########################################################################
 # End alt_cmds package
 # ###########################################################################
@@ -605,20 +609,21 @@ remove_pid_file() {
 # ###########################################################################
 
 
+
 set -u
 
-CMD_GDB="$(which gdb)"
-CMD_IOSTAT="$(which iostat)"
-CMD_MPSTAT="$(which mpstat)"
-CMD_MYSQL="$(which mysql)"
-CMD_MYSQLADMIN="$(which mysqladmin)"
-CMD_OPCONTROL="$(which opcontrol)"
-CMD_OPREPORT="$(which opreport)"
-CMD_PMAP="$(which pmap)"
-CMD_STRACE="$(which strace)"
-CMD_SYSCTL="$(which sysctl)"
-CMD_TCPDUMP="$(which tcpdump)"
-CMD_VMSTAT="$(which vmstat)"
+CMD_GDB="$(_which gdb)"
+CMD_IOSTAT="$(_which iostat)"
+CMD_MPSTAT="$(_which mpstat)"
+CMD_MYSQL="$(_which mysql)"
+CMD_MYSQLADMIN="$(_which mysqladmin)"
+CMD_OPCONTROL="$(_which opcontrol)"
+CMD_OPREPORT="$(_which opreport)"
+CMD_PMAP="$(_which pmap)"
+CMD_STRACE="$(_which strace)"
+CMD_SYSCTL="$(_which sysctl)"
+CMD_TCPDUMP="$(_which tcpdump)"
+CMD_VMSTAT="$(_which vmstat)"
 
 [ -z "$CMD_SYSCTL" -a -x "/sbin/sysctl" ] && CMD_SYSCTL="/sbin/sysctl"
 
@@ -626,7 +631,7 @@ collect() {
    local d="$1"  # directory to save results in
    local p="$2"  # prefix for each result file
 
-   local mysqld_pid=$(_pidof mysqld | awk '{print $1; exit;}')
+   local mysqld_pid=$(_pidof mysqld | head -n1)
 
    if [ "$CMD_PMAP" -a "$mysqld_pid" ]; then
       if $CMD_PMAP --help 2>&1 | grep -- -x >/dev/null 2>&1 ; then
@@ -787,7 +792,7 @@ collect() {
 
       $CMD_OPCONTROL --save=pt_collect_$p
 
-      local mysqld_path=$(which mysqld);
+      local mysqld_path=$(_which mysqld);
       if [ "$mysqld_path" -a -f "$mysqld_path" ]; then
          $CMD_OPREPORT            \
             --demangle=smart      \
diff --git a/lib/bash/alt_cmds.sh b/lib/bash/alt_cmds.sh
index e0d96e64..723d75b8 100644
--- a/lib/bash/alt_cmds.sh
+++ b/lib/bash/alt_cmds.sh
@@ -43,6 +43,12 @@ _lsof() {
    fi
 }
 
+_which() {
+   # which on CentOS is aliased to a cmd that prints extra stuff.
+   # Also, if the cmd isn't found, a msg is printed to stderr.
+   [ -x /usr/bin/which ] && /usr/bin/which "$1" 2>/dev/null | awk '{print $1}'
+}
+
 # ###########################################################################
 # End alt_cmds package
 # ###########################################################################
diff --git a/lib/bash/collect.sh b/lib/bash/collect.sh
index ed303bcb..ee1b5965 100644
--- a/lib/bash/collect.sh
+++ b/lib/bash/collect.sh
@@ -21,21 +21,25 @@
 # Package: collect
 # collect collects system information.
 
+# XXX
+# THIS LIB REQUIRES log_warn_die.sh, safeguards.sh, and alt_cmds.sh!
+# XXX
+
 set -u
 
 # Global variables.
-CMD_GDB="$(which gdb)"
-CMD_IOSTAT="$(which iostat)"
-CMD_MPSTAT="$(which mpstat)"
-CMD_MYSQL="$(which mysql)"
-CMD_MYSQLADMIN="$(which mysqladmin)"
-CMD_OPCONTROL="$(which opcontrol)"
-CMD_OPREPORT="$(which opreport)"
-CMD_PMAP="$(which pmap)"
-CMD_STRACE="$(which strace)"
-CMD_SYSCTL="$(which sysctl)"
-CMD_TCPDUMP="$(which tcpdump)"
-CMD_VMSTAT="$(which vmstat)"
+CMD_GDB="$(_which gdb)"
+CMD_IOSTAT="$(_which iostat)"
+CMD_MPSTAT="$(_which mpstat)"
+CMD_MYSQL="$(_which mysql)"
+CMD_MYSQLADMIN="$(_which mysqladmin)"
+CMD_OPCONTROL="$(_which opcontrol)"
+CMD_OPREPORT="$(_which opreport)"
+CMD_PMAP="$(_which pmap)"
+CMD_STRACE="$(_which strace)"
+CMD_SYSCTL="$(_which sysctl)"
+CMD_TCPDUMP="$(_which tcpdump)"
+CMD_VMSTAT="$(_which vmstat)"
 
 # Try to find command manually.
 [ -z "$CMD_SYSCTL" -a -x "/sbin/sysctl" ] && CMD_SYSCTL="/sbin/sysctl"
@@ -45,7 +49,7 @@ collect() {
    local p="$2"  # prefix for each result file
 
    # Get pidof mysqld.
-   local mysqld_pid=$(_pidof mysqld | awk '{print $1; exit;}')
+   local mysqld_pid=$(_pidof mysqld | head -n1)
 
    # Get memory allocation info before anything else.
    if [ "$CMD_PMAP" -a "$mysqld_pid" ]; then
@@ -243,7 +247,7 @@ collect() {
 
       # Attempt to generate a report; if this fails, then just tell the user
       # how to generate the report.
-      local mysqld_path=$(which mysqld);
+      local mysqld_path=$(_which mysqld);
       if [ "$mysqld_path" -a -f "$mysqld_path" ]; then
          $CMD_OPREPORT            \
             --demangle=smart      \