tools/fix_date.sh

   1 #!/bin/sh
   2
   3 # usage: fix_date.sh <filename> [<filename>..]
   4 # It will replace the Date: value w/ the one picked up from more recent
   5 # Received: field if this field resides in one line. Otherwise, it will
   6 # take the file modification time (using a RFC 2822-compliant form).
   7 # If no X-Original-Date already exist, the former Date value will be set
   8 # in such field.
   9
  10 VERSION="0.0.4"
  11
  12
  13 function version()
  14 {
  15         echo "$VERSION"
  16         exit 0
  17 }
  18
  19 function usage()
  20 {
  21         echo "usage:"
  22         echo "  ${0##*/} [<switches>] <filename> [<filename> ..]"
  23         echo "switches:"
  24         echo "  --help     display this help then exit"
  25         echo "  --version  display version information then exit"
  26         echo "  --force    always force (re-)writing of Date: header"
  27         echo "  --rfc      force re-writing of Date: header when it's not RFC-compliant"
  28         echo "  --debug    turn on debug information (be more verbose)"
  29         echo "  --strict   use RFC-strict matching patterns for dates"
  30         echo "  --         end of switches (in case a filename starts with a -)"
  31         exit $1
  32 }
  33
  34 function date_valid()
  35 {
  36         test $STRICT -eq 1 && \
  37                 REGEXP="$DATE_REGEXP_STRICT" || \
  38                 REGEXP="$DATE_REGEXP"
  39
  40         echo "$1" | grep -qEim 1 "$REGEXP"
  41         DATE_VALID=$?
  42 }
  43
  44 # use --force to always (re-)write the Date header
  45 # otherwise, the Date header will be written if only it doesn't exist
  46 FORCE=0
  47 # use --rfc to (re-)write the Date header when it's not RFC-compliant
  48 # otherwise, the Date header will be written if only it doesn't exist
  49 RFC=0
  50 # use --debug to display more information about what's performed
  51 DEBUG=0
  52 # use --strict to use strict matching patterns for date validation
  53 STRICT=0
  54 # 0 = valid, always valid until --strict is used, then date_valid overrides this value
  55 DATE_VALID=0
  56
  57 while [ -n "$1" ]
  58 do
  59         case "$1" in
  60         --help)         usage 0;;
  61         --version)      version;;
  62         --force)        FORCE=1;;
  63         --debug)        DEBUG=1;;
  64         --rfc)          RFC=1;;
  65         --strict)       STRICT=1;;
  66         --)                     shift
  67                                 break;;
  68         -*)                     echo "error: unrecognized switch '$1'"
  69                                 usage 1;;
  70         *)                      break;;
  71         esac
  72         shift
  73 done
  74
  75 if [ $FORCE -eq 1 -a $RFC -eq 1 ]
  76 then
  77         echo "error: use either --force or --rfc, but not both at the same time"
  78         usage 1
  79 fi
  80
  81 test $# -lt 1 && \
  82         usage 1
  83
  84 TMP="/tmp/${0##*/}.tmp"
  85
  86 DATE_REGEXP="( (Mon|Tue|Wed|Thu|Fri|Sat|Sun),)? [0-9]+ (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dev) [0-9]+ [0-9]+:[0-9]+:[0-9}+ [-+][0-9]+"
  87 DATE_REGEXP_STRICT="(Mon|Tue|Wed|Thu|Fri|Sat|Sun), [0-9]+ (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dev) [0-9]+ [0-9]+:[0-9]+:[0-9}+ [-+][0-9]+"
  88
  89 while [ -n "$1" ]
  90 do
  91         # skip if file is empty or doesn't exist
  92         if [ ! -s "$1" ]
  93         then
  94                 shift
  95                 continue
  96         fi
  97
  98         X_ORIGINAL_DATE=$(grep -Eim 1 '^X-Original-Date: ' "$1" | cut -d ':' -f 2-)
  99         DATE=$(grep -Eim 1 '^Date: ' "$1" | cut -d ':' -f 2-)
 100         test $STRICT -eq 1 && \
 101                 RECEIVED_DATE=$(grep -Eim 1 ";$DATE_REGEXP" "$1" | cut -d ';' -f 2) || \
 102                 RECEIVED_DATE=$(grep -Eim 1 "; $DATE_REGEXP_STRICT" "$1" | cut -d ';' -f 2)
 103         FILE_DATE=$(ls -l --time-style="+%a, %d %b %Y %X %z" "$1" | tr -s ' ' ' ' | cut -d ' ' -f 6-11)
 104         # we could also use the system date as a possible replacement
 105         #SYSTEM_DATE="$(date -R)"
 106
 107         # determine which replacement date to use
 108         if [ -z "$RECEIVED_DATE" ]
 109         then
 110                 # don't forget the leading whitespace here
 111                 REPLACEMENT_DATE=" $FILE_DATE"
 112                 REPLACEMENT="file date"
 113 #               REPLACEMENT_DATE=" $SYSTEM_DATE"
 114 #               REPLACEMENT="system date"
 115         else
 116                 REPLACEMENT_DATE="$RECEIVED_DATE"
 117                 REPLACEMENT="received date"
 118         fi
 119
 120         # ensure that a X-Original-Date is set (but don't override it)
 121         if [ -z "$X_ORIGINAL_DATE" ]
 122         then
 123                 if [ -z "$DATE" ]
 124                 then
 125                         echo "X-Original-Date:$REPLACEMENT_DATE" > "$TMP"
 126                 else
 127                         test $FORCE -eq 1 && \
 128                                 echo "X-Original-Date:$DATE" > "$TMP"
 129                 fi
 130         else
 131                 :> "$TMP"
 132         fi
 133
 134         # replace/set the date and write all lines
 135         test $RFC -eq 1 && \
 136                 date_valid "$DATE"
 137         if [ -z "$DATE" ]
 138         then
 139                 test $DEBUG -eq 1 && \
 140                         echo "$1: date not found, using $REPLACEMENT now"
 141                 echo "Date:$REPLACEMENT_DATE" >> "$TMP"
 142                 cat "$1" >> "$TMP"
 143         else
 144                 if [ $FORCE -eq 1 ]
 145                 then
 146                         test $DEBUG -eq 1 && \
 147                                 echo "$1: date already found, replacing with $REPLACEMENT"
 148                         sed "s/^Date: .*/Date:$REPLACEMENT_DATE/" "$1" >> "$TMP"
 149                 else
 150                         if [ $RFC -eq 1 ]
 151                         then
 152                                 if [ $DATE_VALID -ne 0 ]
 153                                 then
 154                                         test $DEBUG -eq 1 && \
 155                                                 echo "$1: date already found but not RFC-compliant, replacing with $REPLACEMENT"
 156                                         sed "s/^Date: .*/Date:$REPLACEMENT_DATE/" "$1" >> "$TMP"
 157                                 else
 158                                         test $DEBUG -eq 1 && \
 159                                                 echo "$1: date already found and RFC-compliant, skipping"
 160                                         cat "$1" >> "$TMP"
 161                                 fi
 162                         else
 163                                 test $DEBUG -eq 1 && \
 164                                         echo "$1: date already found, skipping"
 165                                 cat "$1" >> "$TMP"
 166                         fi
 167                 fi
 168         fi
 169
 170         # uncomment the following line to backup the original file
 171         #mv -f "$1" "$1.bak"
 172
 173         mv -f "$TMP" "$1"
 174         if [ $? -ne 0 ]
 175         then
 176                 echo "error while moving '$TMP' to '$1'"
 177                 exit 1
 178         fi
 179
 180         shift
 181 done
 182 exit 0