strings.subr revision 252980
1238438Sdteskeif [ ! "$_STRINGS_SUBR" ]; then _STRINGS_SUBR=1 2238438Sdteske# 3247280Sdteske# Copyright (c) 2006-2013 Devin Teske 4252980Sdteske# 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 252980 2013-07-07 18:21:30Z 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 54250701Sdteske# f_snprintf $var_to_set $size $format ... 55250701Sdteske# 56250701Sdteske# Similar to snprintf(3), write at most $size number of bytes into $var_to_set 57250701Sdteske# using printf(1) syntax (`$format ...'). The value of $var_to_set is NULL 58250701Sdteske# unless at-least one byte is stored from the output. 59250701Sdteske# 60250701Sdteskef_snprintf() 61250701Sdteske{ 62250701Sdteske local __var_to_set="$1" __size="$2" 63250701Sdteske shift 2 # var_to_set/size 64250701Sdteske eval "$__var_to_set"=\$\( printf \"\$@\" \| awk -v max=\"\$__size\" \'' 65250701Sdteske { 66250701Sdteske len = length($0) 67250701Sdteske max -= len 68250701Sdteske print substr($0,0,(max > 0 ? len : max + len)) 69250701Sdteske if ( max < 0 ) exit 70250701Sdteske max-- 71250701Sdteske }'\' \) 72250701Sdteske} 73250701Sdteske 74251278Sdteske# f_vsnprintf $var_to_set $size $format $format_args 75251278Sdteske# 76251278Sdteske# Similar to vsnprintf(3), write at most $size number of bytes into $var_to_set 77251278Sdteske# using printf(1) syntax (`$format $format_args'). The value of $var_to_set is 78251278Sdteske# NULL unless at-least one byte is stored from the output. 79251278Sdteske# 80251278Sdteske# Example 1: 81251278Sdteske# 82251278Sdteske# limit=7 format="%s" 83251278Sdteske# format_args="'abc 123'" # 3-spaces between abc and 123 84251278Sdteske# f_vsnprintf foo $limit "$format" "$format_args" # foo=[abc 1] 85251278Sdteske# 86251278Sdteske# Example 2: 87251278Sdteske# 88251278Sdteske# limit=12 format="%s %s" 89251278Sdteske# format_args=" 'doghouse' 'foxhound' " 90251278Sdteske# # even more spaces added to illustrate escape-method 91251278Sdteske# f_vsnprintf foo $limit "$format" "$format_args" # foo=[doghouse fox] 92251278Sdteske# 93251278Sdteske# Example 3: 94251278Sdteske# 95251278Sdteske# limit=13 format="%s %s" 96251278Sdteske# f_shell_escape arg1 'aaa"aaa' # arg1=[aaa"aaa] (no change) 97251278Sdteske# f_shell_escape arg2 "aaa'aaa" # arg2=[aaa'\''aaa] (escaped s-quote) 98251278Sdteske# format_args="'$arg1' '$arg2'" # use single-quotes to surround args 99251278Sdteske# f_vsnprintf foo $limit "$format" "$format_args" # foo=[aaa"aaa aaa'a] 100251278Sdteske# 101251278Sdteske# In all of the above examples, the call to f_vsnprintf() does not change. Only 102251278Sdteske# the contents of $limit, $format, and $format_args changes in each example. 103251278Sdteske# 104251278Sdteskef_vsnprintf() 105251278Sdteske{ 106251278Sdteske eval f_snprintf \"\$1\" \"\$2\" \"\$3\" $4 107251278Sdteske} 108251278Sdteske 109238438Sdteske# f_longest_line_length 110238438Sdteske# 111238438Sdteske# Simple wrapper to an awk(1) script to print the length of the longest line of 112238438Sdteske# input (read from stdin). Supports the newline escape-sequence `\n' for 113238438Sdteske# splitting a single line into multiple lines. 114238438Sdteske# 115238438Sdteskef_longest_line_length_awk=' 116238438SdteskeBEGIN { longest = 0 } 117238438Sdteske{ 118238438Sdteske if (split($0, lines, /\\n/) > 1) 119238438Sdteske { 120238438Sdteske for (n in lines) 121238438Sdteske { 122238438Sdteske len = length(lines[n]) 123238438Sdteske longest = ( len > longest ? len : longest ) 124238438Sdteske } 125238438Sdteske } 126238438Sdteske else 127238438Sdteske { 128238438Sdteske len = length($0) 129238438Sdteske longest = ( len > longest ? len : longest ) 130238438Sdteske } 131238438Sdteske} 132238438SdteskeEND { print longest } 133238438Sdteske' 134238438Sdteskef_longest_line_length() 135238438Sdteske{ 136238438Sdteske awk "$f_longest_line_length_awk" 137238438Sdteske} 138238438Sdteske 139238438Sdteske# f_number_of_lines 140238438Sdteske# 141238438Sdteske# Simple wrapper to an awk(1) script to print the number of lines read from 142238438Sdteske# stdin. Supports newline escape-sequence `\n' for splitting a single line into 143238438Sdteske# multiple lines. 144238438Sdteske# 145238438Sdteskef_number_of_lines_awk=' 146238438SdteskeBEGIN { num_lines = 0 } 147238438Sdteske{ 148241700Sdteske num_lines += split(" "$0, unused, /\\n/) 149238438Sdteske} 150238438SdteskeEND { print num_lines } 151238438Sdteske' 152238438Sdteskef_number_of_lines() 153238438Sdteske{ 154238438Sdteske awk "$f_number_of_lines_awk" 155238438Sdteske} 156238438Sdteske 157238438Sdteske# f_isinteger $arg 158238438Sdteske# 159238438Sdteske# Returns true if argument is a positive/negative whole integer. 160238438Sdteske# 161238438Sdteskef_isinteger() 162238438Sdteske{ 163238438Sdteske local arg="$1" 164238438Sdteske 165238438Sdteske # Prevent division-by-zero 166238438Sdteske [ "$arg" = "0" ] && return $SUCCESS 167238438Sdteske 168238438Sdteske # Attempt to perform arithmetic divison (an operation which will exit 169238438Sdteske # with error unless arg is a valid positive/negative whole integer). 170238438Sdteske # 171240783Sdteske ( : $((0/$arg)) ) > /dev/null 2>&1 172238438Sdteske} 173238438Sdteske 174247280Sdteske# f_uriencode [$text] 175247280Sdteske# 176247280Sdteske# Encode $text for the purpose of embedding safely into a URL. Non-alphanumeric 177247280Sdteske# characters are converted to `%XX' sequence where XX represents the hexa- 178247280Sdteske# decimal ordinal of the non-alphanumeric character. If $text is missing, data 179247280Sdteske# is instead read from standard input. 180247280Sdteske# 181247280Sdteskef_uriencode_awk=' 182247280SdteskeBEGIN { 183247280Sdteske output = "" 184247280Sdteske for (n = 0; n < 256; n++) pack[sprintf("%c", n)] = sprintf("%%%02x", n) 185247280Sdteske} 186247280Sdteske{ 187247280Sdteske sline = "" 188247280Sdteske slen = length($0) 189247280Sdteske for (n = 1; n <= slen; n++) { 190247280Sdteske char = substr($0, n, 1) 191247280Sdteske if ( char !~ /^[[:alnum:]_]$/ ) char = pack[char] 192247280Sdteske sline = sline char 193247280Sdteske } 194247280Sdteske output = output ( output ? "%0a" : "" ) sline 195247280Sdteske} 196247280SdteskeEND { print output } 197247280Sdteske' 198247280Sdteskef_uriencode() 199247280Sdteske{ 200247280Sdteske if [ $# -gt 0 ]; then 201247280Sdteske echo "$1" | awk "$f_uriencode_awk" 202247280Sdteske else 203247280Sdteske awk "$f_uriencode_awk" 204247280Sdteske fi 205247280Sdteske} 206247280Sdteske 207247280Sdteske# f_uridecode [$text] 208247280Sdteske# 209247280Sdteske# Decode $text from a URI. Encoded characters are converted from their `%XX' 210247280Sdteske# sequence into original unencoded ASCII sequences. If $text is missing, data 211247280Sdteske# is instead read from standard input. 212247280Sdteske# 213247280Sdteskef_uridecode_awk=' 214247280SdteskeBEGIN { for (n = 0; n < 256; n++) chr[n] = sprintf("%c", n) } 215247280Sdteske{ 216247280Sdteske sline = "" 217247280Sdteske slen = length($0) 218247280Sdteske for (n = 1; n <= slen; n++) 219247280Sdteske { 220247280Sdteske seq = substr($0, n, 3) 221247280Sdteske if ( seq ~ /^%[[:xdigit:]][[:xdigit:]]$/ ) { 222247280Sdteske hex = substr(seq, 2, 2) 223247280Sdteske sline = sline chr[sprintf("%u", "0x"hex)] 224247280Sdteske n += 2 225247280Sdteske } else 226247280Sdteske sline = sline substr(seq, 1, 1) 227247280Sdteske } 228247280Sdteske print sline 229247280Sdteske} 230247280Sdteske' 231247280Sdteskef_uridecode() 232247280Sdteske{ 233247280Sdteske if [ $# -gt 0 ]; then 234247280Sdteske echo "$1" | awk "$f_uridecode_awk" 235247280Sdteske else 236247280Sdteske awk "$f_uridecode_awk" 237247280Sdteske fi 238247280Sdteske} 239247280Sdteske 240249751Sdteske# f_replaceall $string $find $replace [$var_to_set] 241249751Sdteske# 242250702Sdteske# Replace all occurrences of $find in $string with $replace. If $var_to_set is 243249751Sdteske# either missing or NULL, the variable name is produced on standard out for 244249751Sdteske# capturing in a sub-shell (which is less recommended due to performance 245249751Sdteske# degradation). 246249751Sdteske# 247249751Sdteskef_replaceall() 248249751Sdteske{ 249249751Sdteske local __left="" __right="$1" 250249751Sdteske local __find="$2" __replace="$3" __var_to_set="$4" 251249751Sdteske while :; do 252249751Sdteske case "$__right" in *$__find*) 253249751Sdteske __left="$__left${__right%%$__find*}$__replace" 254249751Sdteske __right="${__right#*$__find}" 255249751Sdteske continue 256249751Sdteske esac 257249751Sdteske break 258249751Sdteske done 259249751Sdteske __left="$__left${__right#*$__find}" 260249751Sdteske if [ "$__var_to_set" ]; then 261249751Sdteske setvar "$__var_to_set" "$__left" 262249751Sdteske else 263249751Sdteske echo "$__left" 264249751Sdteske fi 265249751Sdteske} 266249751Sdteske 267249751Sdteske# f_str2varname $string [$var_to_set] 268249751Sdteske# 269249751Sdteske# Convert a string into a suitable value to be used as a variable name 270249751Sdteske# by converting unsuitable characters into the underscrore [_]. If $var_to_set 271249751Sdteske# is either missing or NULL, the variable name is produced on standard out for 272249751Sdteske# capturing in a sub-shell (which is less recommended due to performance 273249751Sdteske# degradation). 274249751Sdteske# 275249751Sdteskef_str2varname() 276249751Sdteske{ 277249751Sdteske local __string="$1" __var_to_set="$2" 278249751Sdteske f_replaceall "$__string" "[!$VALID_VARNAME_CHARS]" "_" "$__var_to_set" 279249751Sdteske} 280249751Sdteske 281249751Sdteske# f_shell_escape $string [$var_to_set] 282249751Sdteske# 283249751Sdteske# Escape $string for shell eval statement(s) by replacing all single-quotes 284249751Sdteske# with a special sequence that creates a compound string when interpolated 285249751Sdteske# by eval with surrounding single-quotes. 286249751Sdteske# 287249751Sdteske# For example: 288249751Sdteske# 289249751Sdteske# foo="abc'123" 290249751Sdteske# f_shell_escape "$foo" bar # bar=[abc'\''123] 291251272Sdteske# eval echo \'$bar\' # produces abc'123 292249751Sdteske# 293249751Sdteske# This is helpful when processing an argument list that has to retain its 294249751Sdteske# escaped structure for later evaluations. 295249751Sdteske# 296249751Sdteske# WARNING: Surrounding single-quotes are not added; this is the responsibility 297249751Sdteske# of the code passing the escaped values to eval (which also aids readability). 298249751Sdteske# 299249751Sdteskef_shell_escape() 300249751Sdteske{ 301249751Sdteske local __string="$1" __var_to_set="$2" 302249751Sdteske f_replaceall "$__string" "'" "'\\''" "$__var_to_set" 303249751Sdteske} 304249751Sdteske 305249751Sdteske# f_shell_unescape $string [$var_to_set] 306249751Sdteske# 307249751Sdteske# The antithesis of f_shell_escape(), this function takes an escaped $string 308249751Sdteske# and expands it. 309249751Sdteske# 310249751Sdteske# For example: 311249751Sdteske# 312249751Sdteske# foo="abc'123" 313249751Sdteske# f_shell_escape "$foo" bar # bar=[abc'\''123] 314249751Sdteske# f_shell_unescape "$bar" # produces abc'123 315249751Sdteske# 316249751Sdteskef_shell_unescape() 317249751Sdteske{ 318249751Sdteske local __string="$1" __var_to_set="$2" 319249751Sdteske f_replaceall "$__string" "'\\''" "'" "$__var_to_set" 320249751Sdteske} 321249751Sdteske 322249751Sdteske############################################################ MAIN 323249751Sdteske 324244675Sdteskef_dprintf "%s: Successfully loaded." strings.subr 325244675Sdteske 326238438Sdteskefi # ! $_STRINGS_SUBR 327