strings.subr revision 249751
1238438Sdteskeif [ ! "$_STRINGS_SUBR" ]; then _STRINGS_SUBR=1 2238438Sdteske# 3247280Sdteske# Copyright (c) 2006-2013 Devin Teske 4238438Sdteske# All Rights Reserved. 5238438Sdteske# 6238438Sdteske# Redistribution and use in source and binary forms, with or without 7238438Sdteske# modification, are permitted provided that the following conditions 8238438Sdteske# are met: 9238438Sdteske# 1. Redistributions of source code must retain the above copyright 10238438Sdteske# notice, this list of conditions and the following disclaimer. 11238438Sdteske# 2. Redistributions in binary form must reproduce the above copyright 12238438Sdteske# notice, this list of conditions and the following disclaimer in the 13238438Sdteske# documentation and/or other materials provided with the distribution. 14238438Sdteske# 15238438Sdteske# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16238438Sdteske# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING BUT NOT LIMITED TO, THE 17238438Sdteske# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18238438Sdteske# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19238438Sdteske# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20238438Sdteske# DAMAGES (INLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21238438Sdteske# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22238438Sdteske# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23238438Sdteske# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24238438Sdteske# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25238438Sdteske# SUCH DAMAGE. 26238438Sdteske# 27238438Sdteske# $FreeBSD: head/usr.sbin/bsdconfig/share/strings.subr 249751 2013-04-22 05:52:06Z dteske $ 28249751Sdteske# 29249751Sdteske############################################################ GLOBALS 30238438Sdteske 31249751Sdteske# 32249751Sdteske# Valid characters that can appear in an sh(1) variable name 33249751Sdteske# 34249751Sdteske# Please note that the character ranges A-Z and a-z should be avoided because 35249751Sdteske# these can include accent characters (which are not valid in a variable name). 36249751Sdteske# For example, A-Z matches any character that sorts after A but before Z, 37249751Sdteske# including A and Z. Although ASCII order would make more sense, that is not 38249751Sdteske# how it works. 39249751Sdteske# 40249751SdteskeVALID_VARNAME_CHARS="0-9ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz_" 41249751Sdteske 42249751Sdteske############################################################ FUNCTIONS 43249751Sdteske 44238438Sdteske# f_substr "$string" $start [ $length ] 45238438Sdteske# 46238438Sdteske# Simple wrapper to awk(1)'s `substr' function. 47238438Sdteske# 48238438Sdteskef_substr() 49238438Sdteske{ 50238438Sdteske local string="$1" start="${2:-0}" len="${3:-0}" 51238438Sdteske echo "$string" | awk "{ print substr(\$0, $start, $len) }" 52238438Sdteske} 53238438Sdteske 54238438Sdteske# f_longest_line_length 55238438Sdteske# 56238438Sdteske# Simple wrapper to an awk(1) script to print the length of the longest line of 57238438Sdteske# input (read from stdin). Supports the newline escape-sequence `\n' for 58238438Sdteske# splitting a single line into multiple lines. 59238438Sdteske# 60238438Sdteskef_longest_line_length_awk=' 61238438SdteskeBEGIN { longest = 0 } 62238438Sdteske{ 63238438Sdteske if (split($0, lines, /\\n/) > 1) 64238438Sdteske { 65238438Sdteske for (n in lines) 66238438Sdteske { 67238438Sdteske len = length(lines[n]) 68238438Sdteske longest = ( len > longest ? len : longest ) 69238438Sdteske } 70238438Sdteske } 71238438Sdteske else 72238438Sdteske { 73238438Sdteske len = length($0) 74238438Sdteske longest = ( len > longest ? len : longest ) 75238438Sdteske } 76238438Sdteske} 77238438SdteskeEND { print longest } 78238438Sdteske' 79238438Sdteskef_longest_line_length() 80238438Sdteske{ 81238438Sdteske awk "$f_longest_line_length_awk" 82238438Sdteske} 83238438Sdteske 84238438Sdteske# f_number_of_lines 85238438Sdteske# 86238438Sdteske# Simple wrapper to an awk(1) script to print the number of lines read from 87238438Sdteske# stdin. Supports newline escape-sequence `\n' for splitting a single line into 88238438Sdteske# multiple lines. 89238438Sdteske# 90238438Sdteskef_number_of_lines_awk=' 91238438SdteskeBEGIN { num_lines = 0 } 92238438Sdteske{ 93241700Sdteske num_lines += split(" "$0, unused, /\\n/) 94238438Sdteske} 95238438SdteskeEND { print num_lines } 96238438Sdteske' 97238438Sdteskef_number_of_lines() 98238438Sdteske{ 99238438Sdteske awk "$f_number_of_lines_awk" 100238438Sdteske} 101238438Sdteske 102238438Sdteske# f_isinteger $arg 103238438Sdteske# 104238438Sdteske# Returns true if argument is a positive/negative whole integer. 105238438Sdteske# 106238438Sdteskef_isinteger() 107238438Sdteske{ 108238438Sdteske local arg="$1" 109238438Sdteske 110238438Sdteske # Prevent division-by-zero 111238438Sdteske [ "$arg" = "0" ] && return $SUCCESS 112238438Sdteske 113238438Sdteske # Attempt to perform arithmetic divison (an operation which will exit 114238438Sdteske # with error unless arg is a valid positive/negative whole integer). 115238438Sdteske # 116240783Sdteske ( : $((0/$arg)) ) > /dev/null 2>&1 117238438Sdteske} 118238438Sdteske 119247280Sdteske# f_uriencode [$text] 120247280Sdteske# 121247280Sdteske# Encode $text for the purpose of embedding safely into a URL. Non-alphanumeric 122247280Sdteske# characters are converted to `%XX' sequence where XX represents the hexa- 123247280Sdteske# decimal ordinal of the non-alphanumeric character. If $text is missing, data 124247280Sdteske# is instead read from standard input. 125247280Sdteske# 126247280Sdteskef_uriencode_awk=' 127247280SdteskeBEGIN { 128247280Sdteske output = "" 129247280Sdteske for (n = 0; n < 256; n++) pack[sprintf("%c", n)] = sprintf("%%%02x", n) 130247280Sdteske} 131247280Sdteske{ 132247280Sdteske sline = "" 133247280Sdteske slen = length($0) 134247280Sdteske for (n = 1; n <= slen; n++) { 135247280Sdteske char = substr($0, n, 1) 136247280Sdteske if ( char !~ /^[[:alnum:]_]$/ ) char = pack[char] 137247280Sdteske sline = sline char 138247280Sdteske } 139247280Sdteske output = output ( output ? "%0a" : "" ) sline 140247280Sdteske} 141247280SdteskeEND { print output } 142247280Sdteske' 143247280Sdteskef_uriencode() 144247280Sdteske{ 145247280Sdteske if [ $# -gt 0 ]; then 146247280Sdteske echo "$1" | awk "$f_uriencode_awk" 147247280Sdteske else 148247280Sdteske awk "$f_uriencode_awk" 149247280Sdteske fi 150247280Sdteske} 151247280Sdteske 152247280Sdteske# f_uridecode [$text] 153247280Sdteske# 154247280Sdteske# Decode $text from a URI. Encoded characters are converted from their `%XX' 155247280Sdteske# sequence into original unencoded ASCII sequences. If $text is missing, data 156247280Sdteske# is instead read from standard input. 157247280Sdteske# 158247280Sdteskef_uridecode_awk=' 159247280SdteskeBEGIN { for (n = 0; n < 256; n++) chr[n] = sprintf("%c", n) } 160247280Sdteske{ 161247280Sdteske sline = "" 162247280Sdteske slen = length($0) 163247280Sdteske for (n = 1; n <= slen; n++) 164247280Sdteske { 165247280Sdteske seq = substr($0, n, 3) 166247280Sdteske if ( seq ~ /^%[[:xdigit:]][[:xdigit:]]$/ ) { 167247280Sdteske hex = substr(seq, 2, 2) 168247280Sdteske sline = sline chr[sprintf("%u", "0x"hex)] 169247280Sdteske n += 2 170247280Sdteske } else 171247280Sdteske sline = sline substr(seq, 1, 1) 172247280Sdteske } 173247280Sdteske print sline 174247280Sdteske} 175247280Sdteske' 176247280Sdteskef_uridecode() 177247280Sdteske{ 178247280Sdteske if [ $# -gt 0 ]; then 179247280Sdteske echo "$1" | awk "$f_uridecode_awk" 180247280Sdteske else 181247280Sdteske awk "$f_uridecode_awk" 182247280Sdteske fi 183247280Sdteske} 184247280Sdteske 185249751Sdteske# f_replaceall $string $find $replace [$var_to_set] 186249751Sdteske# 187249751Sdteske# Replace all occurrences of $find in $sting with $replace. If $var_to_set is 188249751Sdteske# either missing or NULL, the variable name is produced on standard out for 189249751Sdteske# capturing in a sub-shell (which is less recommended due to performance 190249751Sdteske# degradation). 191249751Sdteske# 192249751Sdteskef_replaceall() 193249751Sdteske{ 194249751Sdteske local __left="" __right="$1" 195249751Sdteske local __find="$2" __replace="$3" __var_to_set="$4" 196249751Sdteske while :; do 197249751Sdteske case "$__right" in *$__find*) 198249751Sdteske __left="$__left${__right%%$__find*}$__replace" 199249751Sdteske __right="${__right#*$__find}" 200249751Sdteske continue 201249751Sdteske esac 202249751Sdteske break 203249751Sdteske done 204249751Sdteske __left="$__left${__right#*$__find}" 205249751Sdteske if [ "$__var_to_set" ]; then 206249751Sdteske setvar "$__var_to_set" "$__left" 207249751Sdteske else 208249751Sdteske echo "$__left" 209249751Sdteske fi 210249751Sdteske} 211249751Sdteske 212249751Sdteske# f_str2varname $string [$var_to_set] 213249751Sdteske# 214249751Sdteske# Convert a string into a suitable value to be used as a variable name 215249751Sdteske# by converting unsuitable characters into the underscrore [_]. If $var_to_set 216249751Sdteske# is either missing or NULL, the variable name is produced on standard out for 217249751Sdteske# capturing in a sub-shell (which is less recommended due to performance 218249751Sdteske# degradation). 219249751Sdteske# 220249751Sdteskef_str2varname() 221249751Sdteske{ 222249751Sdteske local __string="$1" __var_to_set="$2" 223249751Sdteske f_replaceall "$__string" "[!$VALID_VARNAME_CHARS]" "_" "$__var_to_set" 224249751Sdteske} 225249751Sdteske 226249751Sdteske# f_shell_escape $string [$var_to_set] 227249751Sdteske# 228249751Sdteske# Escape $string for shell eval statement(s) by replacing all single-quotes 229249751Sdteske# with a special sequence that creates a compound string when interpolated 230249751Sdteske# by eval with surrounding single-quotes. 231249751Sdteske# 232249751Sdteske# For example: 233249751Sdteske# 234249751Sdteske# foo="abc'123" 235249751Sdteske# f_shell_escape "$foo" bar # bar=[abc'\''123] 236249751Sdteske# eval echo \'$foo\' # produces abc'123 237249751Sdteske# 238249751Sdteske# This is helpful when processing an argument list that has to retain its 239249751Sdteske# escaped structure for later evaluations. 240249751Sdteske# 241249751Sdteske# WARNING: Surrounding single-quotes are not added; this is the responsibility 242249751Sdteske# of the code passing the escaped values to eval (which also aids readability). 243249751Sdteske# 244249751Sdteskef_shell_escape() 245249751Sdteske{ 246249751Sdteske local __string="$1" __var_to_set="$2" 247249751Sdteske f_replaceall "$__string" "'" "'\\''" "$__var_to_set" 248249751Sdteske} 249249751Sdteske 250249751Sdteske# f_shell_unescape $string [$var_to_set] 251249751Sdteske# 252249751Sdteske# The antithesis of f_shell_escape(), this function takes an escaped $string 253249751Sdteske# and expands it. 254249751Sdteske# 255249751Sdteske# For example: 256249751Sdteske# 257249751Sdteske# foo="abc'123" 258249751Sdteske# f_shell_escape "$foo" bar # bar=[abc'\''123] 259249751Sdteske# f_shell_unescape "$bar" # produces abc'123 260249751Sdteske# 261249751Sdteskef_shell_unescape() 262249751Sdteske{ 263249751Sdteske local __string="$1" __var_to_set="$2" 264249751Sdteske f_replaceall "$__string" "'\\''" "'" "$__var_to_set" 265249751Sdteske} 266249751Sdteske 267249751Sdteske############################################################ MAIN 268249751Sdteske 269244675Sdteskef_dprintf "%s: Successfully loaded." strings.subr 270244675Sdteske 271238438Sdteskefi # ! $_STRINGS_SUBR 272