pkgsrc/mk/subst.mk
rillig 212334d5a8 Don't rely on file(1) to distinguish text files from binary files. This
has proven too unreliable in the past. For example, some Makefile.in
files were classified as "Quake I or II world or extension", just
because they happen to start with the letters "PACK". This method was
also subject to subtle differences in the locale.

The new method counts the number of NUL bytes in the file. It does not
depend on the locale settings. The -c option of wc(1) counts bytes, not
characters, and tr(1), which may interpret multibyte sequences, is
protected by LC_ALL. It should also work with the historical
implementations of tr(1) that could not handle NUL bytes and discarded
them, since this is exactly the intention.

See also:
* http://mail-index.netbsd.org/tech-pkg/2006/07/05/0000.html
* PR 37793
2008-01-18 11:16:08 +00:00

133 lines
4.3 KiB
Makefile

# $NetBSD: subst.mk,v 1.50 2008/01/18 11:16:08 rillig Exp $
#
# This Makefile fragment implements a general text replacement facility.
# Package makefiles define a ``class'', for each of which a particular
# substitution description can be defined. For each class of files, a
# target subst-<class> is created to perform the text replacement.
#
# Package-settable variables:
#
# SUBST_CLASSES
# A list of class names. A new class name must be appended (+=).
#
# SUBST_STAGE.<class>
# "stage" at which we do the text replacement. Should be one of
# {pre,do,post}-{extract,patch,configure,build,install}.
#
# SUBST_MESSAGE.<class>
# The message to display when the substitution is done.
#
# SUBST_FILES.<class>
# A list of file patterns on which to run the substitution;
# the filenames are either absolute or relative to ${WRKSRC}.
#
# SUBST_SED.<class>
# List of sed(1) arguments to run on the specified files. Multiple
# commands can be specified using the -e option of sed.
#
# SUBST_VARS.<class>
# List of variables that are substituted whenever they appear in
# the form @VARNAME@. This is basically a short-cut for
#
# -e 's,@VARNAME@,${VARNAME},g'
#
# also taking care of (most) quoting issues. You can use both
# SUBST_SED and SUBST_VARS in a single class.
#
# SUBST_FILTER_CMD.<class>
# Filter used to perform the actual substitution on the specified
# files. Defaults to ${SED} ${SUBST_SED.<class>}.
#
# SUBST_POSTCMD.<class>
# Command to clean up after sed(1). Defaults to ${RM} -f
# $$file${_SUBST_BACKUP_SUFFIX}. For debugging, set it to ${DO_NADA}.
#
# SUBST_SKIP_TEXT_CHECK.<class>
# By default, each file is checked whether it really is a text file
# before any substitutions are done to it. Since that test is not
# perfect, it can be disabled by setting this variable to "yes".
#
# Keywords: subst
#
_VARGROUPS+= subst
_PKG_VARS.subst= SUBST_CLASSES
.for c in ${SUBST_CLASSES}
. for pv in SUBST_STAGE SUBST_MESSAGE SUBST_FILES SUBST_SED SUBST_VARS \
SUBST_FILTER_CMD SUBST_POSTCMD SUBST_SKIP_TEXT_CHECK
_PKG_VARS.subst+= ${pv}.${c}
. endfor
.endfor
ECHO_SUBST_MSG?= ${STEP_MSG}
# _SUBST_IS_TEXT_FILE returns 0 if $${file} is a text file.
_SUBST_IS_TEXT_FILE?= \
{ nchars=`${WC} -c < "$$file"`; \
notnull=`LC_ALL=C ${TR} -d '\\0' < "$$file" | ${WC} -c`; \
[ "$$nchars" = "$$notnull" ] || ${FALSE} ; \
}
_SUBST_BACKUP_SUFFIX= .subst.sav
.for _class_ in ${SUBST_CLASSES}
_SUBST_COOKIE.${_class_}= ${WRKDIR}/.subst_${_class_}_done
SUBST_FILTER_CMD.${_class_}?= ${SED} ${SUBST_SED.${_class_}}
SUBST_VARS.${_class_}?= # none
. for v in ${SUBST_VARS.${_class_}}
SUBST_FILTER_CMD.${_class_} += -e s,@${v}@,${${v}:S|\\|\\\\|gW:S|,|\\,|gW:S|&|\\\&|gW:Q},g
. endfor
SUBST_POSTCMD.${_class_}?= ${RM} -f "$$tmpfile"
SUBST_SKIP_TEXT_CHECK.${_class_}?= no
.if !empty(SUBST_SKIP_TEXT_CHECK.${_class_}:M[Yy][Ee][Ss])
_SUBST_IS_TEXT_FILE.${_class_}= ${TRUE}
.else
_SUBST_IS_TEXT_FILE.${_class_}= ${_SUBST_IS_TEXT_FILE}
.endif
SUBST_TARGETS+= subst-${_class_}
. if defined(SUBST_STAGE.${_class_})
${SUBST_STAGE.${_class_}}: subst-${_class_}
. else
# SUBST_STAGE.* does not need to be defined.
#PKG_FAIL_REASON+= "SUBST_STAGE missing for ${_class_}."
. endif
.PHONY: subst-${_class_}
subst-${_class_}: ${_SUBST_COOKIE.${_class_}}
${_SUBST_COOKIE.${_class_}}:
. if defined(SUBST_MESSAGE.${_class_})
${RUN} ${ECHO_SUBST_MSG} ${SUBST_MESSAGE.${_class_}:Q}
. endif
${RUN} cd ${WRKSRC:Q}; \
files=${SUBST_FILES.${_class_}:Q}; \
for file in $$files; do \
case $$file in /*) ;; *) file="./$$file";; esac; \
tmpfile="$$file"${_SUBST_BACKUP_SUFFIX:Q}; \
if [ ! -f "$$file" ]; then \
${WARNING_MSG} "[subst.mk:${_class_}] Ignoring non-existent file \"$$file\"."; \
elif ${_SUBST_IS_TEXT_FILE.${_class_}}; then \
${MV} -f "$$file" "$$tmpfile" || exit 1; \
${SUBST_FILTER_CMD.${_class_}} \
< "$$tmpfile" \
> "$$file"; \
if ${TEST} -x "$$tmpfile"; then \
${CHMOD} +x "$$file"; \
fi; \
if ${CMP} -s "$$tmpfile" "$$file"; then \
${INFO_MSG} "[subst.mk:${_class_}] Nothing changed in $$file."; \
${MV} -f "$$tmpfile" "$$file"; \
else \
${SUBST_POSTCMD.${_class_}}; \
${ECHO} "$$file" >> ${.TARGET}; \
fi; \
else \
${WARNING_MSG} "[subst.mk:${_class_}] Ignoring non-text file \"$$file\"."; \
fi; \
done
${RUN} ${TOUCH} ${TOUCH_FLAGS} ${.TARGET:Q}
.endfor