pkgsrc/mk/subst.mk
rillig 913583c370 Fixed subst.mk not to corrupt files
Up to now, using subst.mk may have led to file corruption during active
package development. This happened when a sed(1) command had a syntax
error, in which case the whole sed(1) command was terminated, leaving an
empty original file behind.

This commit changes that behavior by applying the sed(1) commands to
the original file and saving the result in a temporary file. Only
after that succeeded is the original file overwritten.

During this rewrite, SUBST_POSTCMD has been removed, since it was
only used in one place (mk/wrapper), and since it relied on the exact
sequence of the internal commands. No package in either main pkgsrc
or pkgsrc-wip uses this variable right now.
2016-01-31 17:27:41 +00:00

135 lines
4.3 KiB
Makefile

# $NetBSD: subst.mk,v 1.55 2016/01/31 17:27:41 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. When adding new classes to this list, be
# sure to append them (+=) instead of overriding them (=).
#
# 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 before doing the substitution.
#
# SUBST_FILES.<class>
# A list of file patterns on which to run the substitution;
# the filenames are either absolute or relative to ${WRKSRC}.
#
# SUBST_SED.<class>
# List of sed(1) arguments to run on the specified files.
# Multiple commands can be specified using the -e option of sed.
# Do not use non-standard sed options (e.g. -E).
#
# SUBST_VARS.<class>
# List of variables that are substituted whenever they appear in
# the form @VARNAME@. This is basically a short-cut for
#
# -e 's,@VARNAME@,${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_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".
#
# See also:
# PLIST_SUBST
#
# 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_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" = "$$notnull" ] || ${FALSE} ; \
}
_SUBST_BACKUP_SUFFIX= .subst.sav
.for _class_ in ${SUBST_CLASSES}
_SUBST_COOKIE.${_class_}= ${WRKDIR}/.subst_${_class_}_done
SUBST_FILTER_CMD.${_class_}?= ${SED} ${SUBST_SED.${_class_}}
SUBST_VARS.${_class_}?= # none
SUBST_MESSAGE.${_class_}?= Substituting "${_class_}" in ${SUBST_FILES.${_class_}}
. for v in ${SUBST_VARS.${_class_}}
SUBST_FILTER_CMD.${_class_} += -e s,@${v}@,${${v}:S|\\|\\\\|gW:S|,|\\,|gW:S|&|\\\&|gW:Q},g
. endfor
_SUBST_KEEP.${_class_}?= ${DO_NADA}
SUBST_SKIP_TEXT_CHECK.${_class_}?= no
.if !empty(SUBST_SKIP_TEXT_CHECK.${_class_}:M[Yy][Ee][Ss])
_SUBST_IS_TEXT_FILE.${_class_}= ${TRUE}
.else
_SUBST_IS_TEXT_FILE.${_class_}= ${_SUBST_IS_TEXT_FILE}
.endif
SUBST_TARGETS+= subst-${_class_}
. if defined(SUBST_STAGE.${_class_})
${SUBST_STAGE.${_class_}}: subst-${_class_}
. else
# SUBST_STAGE.* does not need to be defined.
#PKG_FAIL_REASON+= "SUBST_STAGE missing for ${_class_}."
. endif
.PHONY: subst-${_class_}
subst-${_class_}: ${_SUBST_COOKIE.${_class_}}
${_SUBST_COOKIE.${_class_}}:
. if !empty(SUBST_MESSAGE.${_class_})
${RUN} ${ECHO_SUBST_MSG} ${SUBST_MESSAGE.${_class_}:Q}
. endif
${RUN} cd ${WRKSRC:Q}; \
files=${SUBST_FILES.${_class_}:Q}; \
for file in $$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 \"$$file\"."; \
elif ${_SUBST_IS_TEXT_FILE.${_class_}}; then \
${SUBST_FILTER_CMD.${_class_}} \
< "$$file" \
> "$$tmpfile"; \
if ${TEST} -x "$$file"; then \
${CHMOD} +x "$$tmpfile"; \
fi; \
if ${CMP} -s "$$tmpfile" "$$file"; then \
${INFO_MSG} "[subst.mk:${_class_}] Nothing changed in $$file."; \
${RM} -f "$$tmpfile"; \
else \
${_SUBST_KEEP.${_class_}}; \
${MV} -f "$$tmpfile" "$$file"; \
${ECHO} "$$file" >> ${.TARGET}; \
fi; \
else \
${WARNING_MSG} "[subst.mk:${_class_}] Ignoring non-text file \"$$file\"."; \
fi; \
done
${RUN} ${TOUCH} ${TOUCH_FLAGS} ${.TARGET:Q}
.endfor