fixes for prunner, log, and checkpid (#17)

* improvements for checkpid, log, and prunner
- removed command logging for prunner, as functions with their own logging would get logged twice. each command sent to prunner should deal with its own logging.
- checkpid now uses to check for duplicate process names and does not read the pid file. this allows processes to start that have lingering pid files. suggestions welcome to make it do both.
- enhanced log safety to prevent hangs on empty pipes.

* updated readme

README.md

@@ -1,13 +1,13 @@
 # bblib
 
-The _"Better BASH Library"_: A set of functions to assist with creating well-written and reliable BASH scripts. The functions are documented in-line within `bblib.bash`, and a simple example that uses it is in `example.bash`.
+The _"Better Bash Library"_: A set of functions to assist with creating well-written and reliable Bash scripts. The functions are documented in-line within `bblib.bash`, and a simple example that uses it is in `example.bash`.
 
 ## Usage
 
-Add this to the top of your BASH script:
+Add this to the top of your Bash script:
 
 ```bash
-source <(wget -qO- https://raw.githubusercontent.com/MrDrMcCoy/bblib/1.1.7/bblib.bash)
+source <(wget -qO- https://raw.githubusercontent.com/MrDrMcCoy/bblib/1.1.8/bblib.bash)
 ```
 
 Alternately, clone this repo locally and use `source` with the full path to `bblib.bash`.
@@ -91,15 +91,14 @@ Once `bblib.bash` is sourced in your script, you may refer to any of its supplie
   - Description: Checks to see if the user running the script matches the desired username and exits on failure.
   - Usage: `requireuser [user]`
 - `bash4check`
-  - Description: Checks to see if you are on BASH 4.0 or above and exits if not.
-  - Usage: Place `bash4check` at the beginning of any function that uses BASH 4+ features.
+  - Description: Checks to see if you are on Bash 4.0 or above and exits if not.
+  - Usage: Place `bash4check` at the beginning of any function that uses Bash 4+ features.
 - `finally`
   - Description: A function that runs extra commands before the script exits
   - Usage: Add actions to its list by running: `FINALCMDS+=("command arg arg")`
 - `checkpid`
-  - Description: Checks to see if another copy of this script is running by maintaining a PID file
+  - Description: Checks to see if another copy of this script is running by checking `ps` and maintaining a PID file.
   - Usage: `checkpid`
-  - Notes: This function only works properly in Linux, as it depends on PROCFS.
 - `prunner`
   - Description: Executes commands in parallel.
   - Usage:
@@ -130,7 +129,7 @@ Once `bblib.bash` is sourced in your script, you may refer to any of its supplie
 - `LOGFILE`
   - Description: Set this to have `log` additionally output to a file.
   - Used by: `log`.
-  - Notes: This will capture debug output if BASH has `set -x`.
+  - Notes: This will capture debug output if Bash has `set -x`.
   - Default: _unset_
 - `PIDFILE`
   - Description: The path to a file for tracking the PID of the script.
@@ -161,8 +160,14 @@ The commands that `bblib.bash` calls out to are listed here, in case you are on
   - Used by: `usage`
 - `fold`
   - Used by: `pprint`
+- `grep`
+  - Used by: `checkpid`
 - `logger`
   - Used by: `log`
+- `ps`
+  - Used by: `checkpid`
+- `rm`
+  - Used by: `checkpid`
 - `tee`
   - Used by: `log`
 - `tr`
@@ -174,8 +179,8 @@ The commands that `bblib.bash` calls out to are listed here, in case you are on
 
 If you would like to extend this library, some resources for advanced usage are available here:
 
-- The BASH Beginners Guide, which is not just for beginners: <https://www.tldp.org/LDP/Bash-Beginners-Guide/html/>
-- The Advanced BASH guide: <http://tldp.org/LDP/abs/html/>
-- The BASH Hackers Wiki has great advanced usage description and examples for BASH: <http://wiki.bash-hackers.org/>
-- BASH Style Guide: <https://google.github.io/styleguide/shell.xml>
+- The Bash Beginners Guide, which is not just for beginners: <https://www.tldp.org/LDP/Bash-Beginners-Guide/html/>
+- The Advanced Bash guide: <http://tldp.org/LDP/abs/html/>
+- The Bash Hackers Wiki has great advanced usage description and examples for Bash: <http://wiki.bash-hackers.org/>
+- Bash Style Guide: <https://google.github.io/styleguide/shell.xml>
 - A very good `getopts` tutorial: <https://sookocheff.com/post/bash/parsing-bash-script-arguments-with-shopts/>

bblib.bash

@@ -78,9 +78,10 @@ uc () {
 hr () {
   # Print horizontal rule
   # Usage: hr [character]
-  local CHARACTER="${1:0:1}"
+  local CHARACTER="${1:--}"
+  local CHARACTER="${CHARACTER:0:1}"
   local -i COLUMNS=${COLUMNS:-$(tput cols)}
-  printf '%*s\n' "${COLUMNS:-80}" '' | tr ' ' "${CHARACTER:--}"
+  printf '%*s\n' "${COLUMNS:-80}" '' | tr ' ' "${CHARACTER}"
 }
 
 log () {
@@ -119,7 +120,7 @@ log () {
   # Send message to logger
   if [ "${NUMERIC_SEVERITY}" -le "${NUMERIC_LOGLEVEL}" ] ; then
     tr '\n' ' ' <<< "${LOGMSG}" | logger -s -p "user.${NUMERIC_SEVERITY}" -t "${LOGTAG} " |& \
-      if [ -n "${LOGFILE:-}" ] ; then
+      if [ -n "${LOGFILE:-}" ] && [ ! -t 0 ] ; then
         tee -a "${LOGFILE}" | pprint ${LOGCOLORS[$NUMERIC_SEVERITY]}
       elif [ ! -t 0 ]; then
         pprint ${LOGCOLORS[$NUMERIC_SEVERITY]} < /dev/stdin
@@ -150,7 +151,7 @@ bash4check () {
   if [ "${BASH_VERSINFO[0]}" -lt 4 ] ; then
     quit "ALERT" "Sorry, you need at least bash version 4 to run this function: ${FUNCNAME[1]}"
   else
-    log "DEBUG" "This script is safe to enable BASH version 4 features"
+    log "DEBUG" "This script is safe to enable Bash version 4 features"
   fi
 }
 
@@ -167,18 +168,12 @@ checkpid () {
   # Check for and maintain pidfile
   # Usage: checkpid
   local PIDFILE="${PIDFILE:-${0}.pid}"
-  if [[ ! -d "/proc/$$" ]]; then
-    quit "ERROR" "This function requires procfs. Are you on Linux?"
-  elif [[ ! -f "${PIDFILE}" ]] ; then
-    echo -n "$$" > "${PIDFILE}"
+  if [[ $( ps ao args | grep -wc "$(basename "$0")" ) -gt 3 ]] ; then
+    quit "ERROR" "Script '$(basename "$0")' is already running, exiting."
+  else
+    echo "$$" > "${PIDFILE}"
     FINALCMDS+=("rm -v ${PIDFILE}")
     log "DEBUG" "PID $$ has no conflicts and has been written to ${PIDFILE}"
-  elif [[ "$( cat "${PIDFILE}" || true )" -ne $$ ]] ; then
-    quit "ERROR" "This script is already running, exiting."
-  elif [[ "$( cat "${PIDFILE}" || true )" -eq $$ ]] ; then
-    log "DEBUG" "PID $$ matches the contents of ${PIDFILE}, proceeding."
-  else
-    quit "ALERT" "Unknown error verifying unique PID."
   fi
 }
 
@@ -261,7 +256,7 @@ prunner () {
   local -i INDEX=0
   until [ ${#PQUEUE[@]} == 0 ] ; do
     if [ "$(jobs -rp | wc -l)" -lt "${THREADS:-8}" ] ; then
-      ${PCMD} ${PQUEUE[$INDEX]} 2> >(log "ERROR") | log "DEBUG" &
+      ${PCMD} ${PQUEUE[$INDEX]}
       unset "PQUEUE[$INDEX]"
       ((INDEX++)) || true
     fi
@@ -273,7 +268,7 @@ prunner () {
 trap finally EXIT
 
 # Trap for killing runaway processes and exiting
-trap "quit 'ALERT' 'Exiting on signal' '3'" SIGINT SIGTERM
+trap "quit 'ALERT' 'Exiting on signal' '3'" INT TERM QUIT HUP
 
 # Trap to capture errors
 trap 'quit "ALERT" "Command failed with exit code $?: $BASH_COMMAND" "$?"' ERR

tests/test.bash

@@ -8,6 +8,12 @@ main () {
 
   log "INFO" "Starting tests"
 
+  # Pid check
+  log "INFO" "Test checkpid"
+  checkpid || true
+  log "INFO" "Test checkpid in second shell"
+  bash "$0" || true & wait
+
   # Test argparser
   log "INFO" "Test argparser with no options"
   bash -c 'source ../bblib.bash ; source test.bash.conf ; argparser' || true
@@ -23,14 +29,28 @@ main () {
   bash -c 'source ../bblib.bash ; source test.bash.conf ; argparser -y' || true
 
   # Test hr
-  log "INFO" "Test hr ="
-  hr =
+  log "INFO" "Test hr"
+  hr
+  hr = | pprint yellow
 
-  # Test lc, uc, and pprint
+  # Test lc, uc, pprint line wrapping
   log "INFO" "Test lc"
-  lc < lorem-ipsum.txt | pprint > lorem-ipsum-lc-pprint.out |& log "DEBUG"
+  head -n1 lorem-ipsum.txt | lc | pprint
   log "INFO" "Test uc"
-  uc < lorem-ipsum.txt | pprint > lorem-ipsum-uc-pprint.out |& log "DEBUG"
+  tail -n1 lorem-ipsum.txt | uc | pprint
+
+  # Test pprint colors
+  log "INFO" "Test pprint"
+  pprint 0 <<< black
+  pprint 1 <<< red
+  pprint 2 <<< green
+  pprint 3 <<< yellow
+  pprint 4 <<< blue
+  pprint 5 <<< magenta
+  pprint 6 <<< cyan
+  pprint 7 <<< white
+  pprint 8 <<< bold
+  pprint 9 <<< underline
 
   # Test shorthand log log loggers
   log_debug "shorthand log_debug test"
@@ -46,12 +66,6 @@ main () {
   log "INFO" "Test bash4check"
   bash4check
 
-  # Pid check
-  log "INFO" "Test checkpid"
-  checkpid || true
-  log "INFO" "Test checkpid in second shell"
-  bash -c 'source ../bblib.bash ; source test.bash.conf ; checkpid' || true
-
   # User check
   log "INFO" "Test requireuser with \$REQUIREUSER"
   bash -c 'source ../bblib.bash ; source test.bash.conf ; requireuser' || true
@@ -71,9 +85,9 @@ main () {
 
   # Parallel test
   log "INFO" "Test prunner gzipping the .out files with arguments for the jobs"
-  prunner -c "gzip -fk" *.out
-  log "INFO" "Test prunner echoing the .out files with stdin for the jobs"
-  find . -maxdepth 1 -type f -name "*.out" | head -n5 | prunner -c "echo found file " -t 6
+  prunner -c "gzip -f" *.out
+  log "INFO" "Test prunner echoing the .gz files with stdin for the jobs"
+  find . -maxdepth 1 -type f -name "*.gz" | head -n5 | prunner -c "echo found file " -t 6
 
   # Add cleanup tasks
   FINALCMDS+=('rm -v *.out')