#!/bin/bash
d1=$(date -d "20110624 03:00:00" +%s)
d2=$(date -d "20110624 10:00:00" +%s)

while read line
do
  date=$(echo $line | awk 'BEGIN{ FS = "[][]" }{ gsub(/\//," ",$2); sub(/:/," ",$2); sub(/-.*/,"",$2); print $2 }')
  date=$(date -d "$date" +%s)
  [[ $date -ge $d1 && $date -le $d2 ]] && echo $line
done < apache.log

#!/bin/bash

# Usage:  scriptname [date1] [date2] logname

# dates should be in the same format as the apache log
# although other formats supported by the date command may work
# (but probably won't since the function strips a single colon from it)

cleandate() {

	local n
	# convert the month to numeric form
	case "$1" in
		*Jan* ) n="${1/Jan/01}" ;;
		*Feb* ) n="${1/Feb/02}" ;;
		*Mar* ) n="${1/Mar/03}" ;;
		*Apr* ) n="${1/Apr/04}" ;;
		*May* ) n="${1/May/05}" ;;
		*Jun* ) n="${1/Jun/06}" ;;
		*Jul* ) n="${1/Jul/07}" ;;
		*Aug* ) n="${1/Aug/08}" ;;
		*Sep* ) n="${1/Sep/09}" ;;
		*Oct* ) n="${1/Oct/10}" ;;
		*Nov* ) n="${1/Nov/11}" ;;
		*Dec* ) n="${1/Dec/12}" ;;
	esac

	# remove first colon from string
	n="${n/:/ }"
	#use date to convert to epoch and print
	date -d "$n" +%s

}

# Take the input dates and process them to epoch with the cleandate function
d1=$( cleandate "$1" )
d2=$( cleandate "$2" )

while read line; do

	# Extract the date for each line.
	# First strip off everything up to the first "[".
	# Then remove everything after the first "]".
	# Finally, straighten up the format with the cleandate function
	date="${line#*[}"
	date="${date%%]*}"
	date=$( cleandate "$date" )

	# If the date falls between d1 and d2, print it
	if [[ $date -ge $d1 && $date -le $d2 ]]; then
		 echo "$line"
	fi

done < "$3"

exit 0