strings.subr revision 294898
1if [ ! "$_STRINGS_SUBR" ]; then _STRINGS_SUBR=1 2# 3# Copyright (c) 2006-2013 Devin Teske 4# All rights reserved. 5# 6# Redistribution and use in source and binary forms, with or without 7# modification, are permitted provided that the following conditions 8# are met: 9# 1. Redistributions of source code must retain the above copyright 10# notice, this list of conditions and the following disclaimer. 11# 2. Redistributions in binary form must reproduce the above copyright 12# notice, this list of conditions and the following disclaimer in the 13# documentation and/or other materials provided with the distribution. 14# 15# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25# SUCH DAMAGE. 26# 27# $FreeBSD: stable/10/usr.sbin/bsdconfig/share/strings.subr 294898 2016-01-27 06:38:03Z dteske $ 28# 29############################################################ INCLUDES 30 31BSDCFG_SHARE="/usr/share/bsdconfig" 32. $BSDCFG_SHARE/common.subr || exit 1 33 34############################################################ GLOBALS 35 36# 37# A Literal newline (for use with f_replace_all(), or IFS, or whatever) 38# 39NL=" 40" # END-QUOTE 41 42# 43# Valid characters that can appear in an sh(1) variable name 44# 45# Please note that the character ranges A-Z and a-z should be avoided because 46# these can include accent characters (which are not valid in a variable name). 47# For example, A-Z matches any character that sorts after A but before Z, 48# including A and Z. Although ASCII order would make more sense, that is not 49# how it works. 50# 51VALID_VARNAME_CHARS="0-9ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz_" 52 53############################################################ FUNCTIONS 54 55# f_substr "$string" $start [$length] 56# 57# Simple wrapper to awk(1)'s `substr' function. 58# 59f_substr() 60{ 61 local string="$1" start="${2:-0}" len="${3:-0}" 62 echo "$string" | awk "{ print substr(\$0, $start, $len) }" 63} 64 65# f_snprintf $var_to_set $size $format [$arguments ...] 66# 67# Similar to snprintf(3), write at most $size number of bytes into $var_to_set 68# using printf(1) syntax (`$format [$arguments ...]'). The value of $var_to_set 69# is NULL unless at-least one byte is stored from the output. 70# 71f_snprintf() 72{ 73 local __var_to_set="$1" __size="$2" 74 shift 2 # var_to_set size 75 eval "$__var_to_set"=\$\( printf -- \"\$@\" \| \ 76 awk -v max=\"\$__size\" \'' 77 { 78 len = length($0) 79 max -= len 80 print substr($0,0,(max > 0 ? len : max + len)) 81 if ( max < 0 ) exit 82 max-- 83 }'\' \) 84} 85 86# f_sprintf $var_to_set $format [$arguments ...] 87# 88# Similar to sprintf(3), write a string into $var_to_set using printf(1) syntax 89# (`$format [$arguments ...]'). 90# 91f_sprintf() 92{ 93 local __var_to_set="$1" 94 shift 1 # var_to_set 95 eval "$__var_to_set"=\$\( printf -- \"\$@\" \) 96} 97 98# f_vsnprintf $var_to_set $size $format $format_args 99# 100# Similar to vsnprintf(3), write at most $size number of bytes into $var_to_set 101# using printf(1) syntax (`$format $format_args'). The value of $var_to_set is 102# NULL unless at-least one byte is stored from the output. 103# 104# Example 1: 105# 106# limit=7 format="%s" 107# format_args="'abc 123'" # 3-spaces between abc and 123 108# f_vsnprintf foo $limit "$format" "$format_args" # foo=[abc 1] 109# 110# Example 2: 111# 112# limit=12 format="%s %s" 113# format_args=" 'doghouse' 'fox' " 114# # even more spaces added to illustrate escape-method 115# f_vsnprintf foo $limit "$format" "$format_args" # foo=[doghouse fox] 116# 117# Example 3: 118# 119# limit=13 format="%s %s" 120# f_shell_escape arg1 'aaa"aaa' # arg1=[aaa"aaa] (no change) 121# f_shell_escape arg2 "aaa'aaa" # arg2=[aaa'\''aaa] (escaped s-quote) 122# format_args="'$arg1' '$arg2'" # use single-quotes to surround args 123# f_vsnprintf foo $limit "$format" "$format_args" # foo=[aaa"aaa aaa'a] 124# 125# In all of the above examples, the call to f_vsnprintf() does not change. Only 126# the contents of $limit, $format, and $format_args changes in each example. 127# 128f_vsnprintf() 129{ 130 eval f_snprintf \"\$1\" \"\$2\" \"\$3\" $4 131} 132 133# f_vsprintf $var_to_set $format $format_args 134# 135# Similar to vsprintf(3), write a string into $var_to_set using printf(1) 136# syntax (`$format $format_args'). 137# 138f_vsprintf() 139{ 140 eval f_sprintf \"\$1\" \"\$2\" $3 141} 142 143# f_longest_line_length 144# 145# Simple wrapper to an awk(1) script to print the length of the longest line of 146# input (read from stdin). Supports the newline escape-sequence `\n' for 147# splitting a single line into multiple lines. 148# 149f_longest_line_length_awk=' 150BEGIN { longest = 0 } 151{ 152 if (split($0, lines, /\\n/) > 1) 153 { 154 for (n in lines) 155 { 156 len = length(lines[n]) 157 longest = ( len > longest ? len : longest ) 158 } 159 } 160 else 161 { 162 len = length($0) 163 longest = ( len > longest ? len : longest ) 164 } 165} 166END { print longest } 167' 168f_longest_line_length() 169{ 170 awk "$f_longest_line_length_awk" 171} 172 173# f_number_of_lines 174# 175# Simple wrapper to an awk(1) script to print the number of lines read from 176# stdin. Supports newline escape-sequence `\n' for splitting a single line into 177# multiple lines. 178# 179f_number_of_lines_awk=' 180BEGIN { num_lines = 0 } 181{ 182 num_lines += split(" "$0, unused, /\\n/) 183} 184END { print num_lines } 185' 186f_number_of_lines() 187{ 188 awk "$f_number_of_lines_awk" 189} 190 191# f_isinteger $arg 192# 193# Returns true if argument is a positive/negative whole integer. 194# 195f_isinteger() 196{ 197 local arg="${1#-}" 198 [ "${arg:-x}" = "${arg%[!0-9]*}" ] 199} 200 201# f_uriencode [$text] 202# 203# Encode $text for the purpose of embedding safely into a URL. Non-alphanumeric 204# characters are converted to `%XX' sequence where XX represents the hexa- 205# decimal ordinal of the non-alphanumeric character. If $text is missing, data 206# is instead read from standard input. 207# 208f_uriencode_awk=' 209BEGIN { 210 output = "" 211 for (n = 0; n < 256; n++) pack[sprintf("%c", n)] = sprintf("%%%02x", n) 212} 213{ 214 sline = "" 215 slen = length($0) 216 for (n = 1; n <= slen; n++) { 217 char = substr($0, n, 1) 218 if ( char !~ /^[[:alnum:]_]$/ ) char = pack[char] 219 sline = sline char 220 } 221 output = output ( output ? "%0a" : "" ) sline 222} 223END { print output } 224' 225f_uriencode() 226{ 227 if [ $# -gt 0 ]; then 228 echo "$1" | awk "$f_uriencode_awk" 229 else 230 awk "$f_uriencode_awk" 231 fi 232} 233 234# f_uridecode [$text] 235# 236# Decode $text from a URI. Encoded characters are converted from their `%XX' 237# sequence into original unencoded ASCII sequences. If $text is missing, data 238# is instead read from standard input. 239# 240f_uridecode_awk=' 241BEGIN { for (n = 0; n < 256; n++) chr[n] = sprintf("%c", n) } 242{ 243 sline = "" 244 slen = length($0) 245 for (n = 1; n <= slen; n++) 246 { 247 seq = substr($0, n, 3) 248 if ( seq ~ /^%[[:xdigit:]][[:xdigit:]]$/ ) { 249 hex = substr(seq, 2, 2) 250 sline = sline chr[sprintf("%u", "0x"hex)] 251 n += 2 252 } else 253 sline = sline substr(seq, 1, 1) 254 } 255 print sline 256} 257' 258f_uridecode() 259{ 260 if [ $# -gt 0 ]; then 261 echo "$1" | awk "$f_uridecode_awk" 262 else 263 awk "$f_uridecode_awk" 264 fi 265} 266 267# f_replaceall $string $find $replace [$var_to_set] 268# 269# Replace all occurrences of $find in $string with $replace. If $var_to_set is 270# either missing or NULL, the variable name is produced on standard out for 271# capturing in a sub-shell (which is less recommended due to performance 272# degradation). 273# 274# To replace newlines or a sequence containing the newline character, use $NL 275# as `\n' is not supported. 276# 277f_replaceall() 278{ 279 local __left="" __right="$1" 280 local __find="$2" __replace="$3" __var_to_set="$4" 281 while :; do 282 case "$__right" in *$__find*) 283 __left="$__left${__right%%$__find*}$__replace" 284 __right="${__right#*$__find}" 285 continue 286 esac 287 break 288 done 289 __left="$__left${__right#*$__find}" 290 if [ "$__var_to_set" ]; then 291 setvar "$__var_to_set" "$__left" 292 else 293 echo "$__left" 294 fi 295} 296 297# f_str2varname $string [$var_to_set] 298# 299# Convert a string into a suitable value to be used as a variable name 300# by converting unsuitable characters into the underscrore [_]. If $var_to_set 301# is either missing or NULL, the variable name is produced on standard out for 302# capturing in a sub-shell (which is less recommended due to performance 303# degradation). 304# 305f_str2varname() 306{ 307 local __string="$1" __var_to_set="$2" 308 f_replaceall "$__string" "[!$VALID_VARNAME_CHARS]" "_" "$__var_to_set" 309} 310 311# f_shell_escape $string [$var_to_set] 312# 313# Escape $string for shell eval statement(s) by replacing all single-quotes 314# with a special sequence that creates a compound string when interpolated 315# by eval with surrounding single-quotes. 316# 317# For example: 318# 319# foo="abc'123" 320# f_shell_escape "$foo" bar # bar=[abc'\''123] 321# eval echo \'$bar\' # produces abc'123 322# 323# This is helpful when processing an argument list that has to retain its 324# escaped structure for later evaluations. 325# 326# WARNING: Surrounding single-quotes are not added; this is the responsibility 327# of the code passing the escaped values to eval (which also aids readability). 328# 329f_shell_escape() 330{ 331 local __string="$1" __var_to_set="$2" 332 f_replaceall "$__string" "'" "'\\''" "$__var_to_set" 333} 334 335# f_shell_unescape $string [$var_to_set] 336# 337# The antithesis of f_shell_escape(), this function takes an escaped $string 338# and expands it. 339# 340# For example: 341# 342# foo="abc'123" 343# f_shell_escape "$foo" bar # bar=[abc'\''123] 344# f_shell_unescape "$bar" # produces abc'123 345# 346f_shell_unescape() 347{ 348 local __string="$1" __var_to_set="$2" 349 f_replaceall "$__string" "'\\''" "'" "$__var_to_set" 350} 351 352# f_expand_number $string [$var_to_set] 353# 354# Unformat $string into a number, optionally to be stored in $var_to_set. This 355# function follows the SI power of two convention. 356# 357# The prefixes are: 358# 359# Prefix Description Multiplier 360# k kilo 1024 361# M mega 1048576 362# G giga 1073741824 363# T tera 1099511627776 364# P peta 1125899906842624 365# E exa 1152921504606846976 366# 367# NOTE: Prefixes are case-insensitive. 368# 369# Upon successful completion, success status is returned; otherwise the number 370# -1 is produced ($var_to_set set to -1 or if $var_to_set is NULL or missing) 371# on standard output. In the case of failure, the error status will be one of: 372# 373# Status Reason 374# 1 Given $string contains no digits 375# 2 An unrecognized prefix was given 376# 3 Result too large to calculate 377# 378f_expand_number() 379{ 380 local __string="$1" __var_to_set="$2" 381 local __cp __num __bshift __maxinput 382 383 # Remove any leading non-digits 384 __string="${__string#${__string%%[0-9]*}}" 385 386 # Store the numbers (no trailing suffix) 387 __num="${__string%%[!0-9]*}" 388 389 # Produce `-1' if string didn't contain any digits 390 if [ ! "$__num" ]; then 391 if [ "$__var_to_set" ]; then 392 setvar "$__var_to_set" -1 393 else 394 echo -1 395 fi 396 return 1 # 1 = "Given $string contains no digits" 397 fi 398 399 # Remove all the leading numbers from the string to get at the prefix 400 __string="${__string#"$__num"}" 401 402 # 403 # Test for invalid prefix (and determine bitshift length) 404 # 405 case "$__string" in 406 ""|[[:space:]]*) # Shortcut 407 if [ "$__var_to_set" ]; then 408 setvar "$__var_to_set" $__num 409 else 410 echo $__num 411 fi 412 return $SUCCESS ;; 413 [Kk]*) __bshift=10 ;; 414 [Mm]*) __bshift=20 ;; 415 [Gg]*) __bshift=30 ;; 416 [Tt]*) __bshift=40 ;; 417 [Pp]*) __bshift=50 ;; 418 [Ee]*) __bshift=60 ;; 419 *) 420 # Unknown prefix 421 if [ "$__var_to_set" ]; then 422 setvar "$__var_to_set" -1 423 else 424 echo -1 425 fi 426 return 2 # 2 = "An unrecognized prefix was given" 427 esac 428 429 # Determine if the wheels fall off 430 __maxinput=$(( 0x7fffffffffffffff >> $__bshift )) 431 if [ $__num -gt $__maxinput ]; then 432 # Input (before expanding) would exceed 64-bit signed int 433 if [ "$__var_to_set" ]; then 434 setvar "$__var_to_set" -1 435 else 436 echo -1 437 fi 438 return 3 # 3 = "Result too large to calculate" 439 fi 440 441 # Shift the number out and produce it 442 __num=$(( $__num << $__bshift )) 443 if [ "$__var_to_set" ]; then 444 setvar "$__var_to_set" $__num 445 else 446 echo $__num 447 fi 448} 449 450############################################################ MAIN 451 452f_dprintf "%s: Successfully loaded." strings.subr 453 454fi # ! $_STRINGS_SUBR 455