Implement platform-independent signal lists

.gitignore

@@ -5,6 +5,10 @@ pcp-htop
 # all object files
 *.o
 
+# intermediate signal lists
+/signals/SignalList.in.i
+/signals/SignalList.in.sorted
+
 # skip all backups
 *.bak
 *~

Makefile.am

@@ -10,6 +10,9 @@ dist_man_MANS = htop.1
 EXTRA_DIST = \
 	$(dist_man_MANS) \
 	autogen.sh \
+	signals/ParseSignals.sed \
+	signals/PrintSignals.sed \
+	signals/SignalList.in.c \
 	htop.desktop \
 	htop.png \
 	htop.svg \
@@ -438,6 +441,24 @@ myhtopplatsources = $(unsupported_platform_sources)
 myhtopplatheaders = $(unsupported_platform_headers)
 endif
 
+# Sorting the signal list at build time
+# -------------------------------------
+
+SUFFIXES = .i
+# Preprocessing a list of signals to get their numbers from the headers.
+.c.i:
+	$(AM_V_GEN)$(CPP) $(AM_CPPFLAGS) $(CPPFLAGS) -o $@ $<
+
+MOSTLYCLEANFILES = signals/SignalList.in.i signals/SignalList.in.sorted
+# Sorting the list of signals by the signal number.
+signals/SignalList.in.sorted: signals/SignalList.in.i $(srcdir)/signals/ParseSignals.sed $(srcdir)/signals/PrintSignals.sed
+	$(AM_V_GEN)$(SED) -f $(srcdir)/signals/ParseSignals.sed signals/SignalList.in.i | LC_COLLATE=C $(SORT) -t'	' -k1n,1 -k2 | $(SED) -f $(srcdir)/signals/PrintSignals.sed > $@
+
+# Building the sorted signal list.
+# This should only add a dependency without inadvertently overriding any
+# Automake-generated rules, because SignalList.o is built using a suffix rule.
+signals/SignalList.$(OBJEXT): signals/SignalList.in.sorted
+
 # ----
 
 htop_SOURCES = $(myhtopplatprogram) $(myhtopheaders) $(myhtopplatheaders) $(myhtopsources) $(myhtopplatsources)

configure.ac

@@ -69,12 +69,23 @@ AC_USE_SYSTEM_EXTENSIONS
 
 AC_PROG_CC
 AM_PROG_CC_C_O
+AC_PROG_CPP
 m4_version_prereq([2.70], [], [AC_PROG_CC_C99])
 AS_IF([test "x$ac_cv_prog_cc_c99" = xno], [AC_MSG_ERROR([htop is written in C99. A newer compiler is required.])])
 
 # ----------------------------------------------------------------------
 
 
+# ----------------------------------------------------------------------
+# Checks for common tools.
+# ----------------------------------------------------------------------
+
+AC_PROG_SED
+AC_PATH_PROG([SORT], [sort], [sort])
+
+# ----------------------------------------------------------------------
+
+
 # ----------------------------------------------------------------------
 # Checks for static build.
 # ----------------------------------------------------------------------

signals/ParseSignals.sed

@@ -0,0 +1,99 @@
+# htop - signals/ParseSignals.sed
+# (C) 2023 htop dev team
+# Released under the GNU GPLv2+, see the COPYING file
+# in the source distribution for its full text.
+
+# Parse a preprocessed C file with a list of signal numbers and names; output
+# the numbers and names in a sortable format.
+
+# The reason why this script exists at all is that the preprocessed C output
+# doesn't correspond line-to-line with the original source file. Among other
+# issues, it contains preprocessor directives with line numbers, which break
+# up the output. To allow sorting the file by signal name at compile time,
+# the preprocessed output has to be "parsed" and reformatted.
+
+# The script should be relatively robust wrt. C compiler output, but it should
+# still be considered a hack. It is possible that unforeseen input breaks it.
+
+# It works by building up each multiline signal entry (number and name) in the
+# hold space until it is complete, postprocessing and printing it. The entry
+# is recognized by the htop_sig{start,mid,end} markers, because these are all
+# but guaranteed not to be mangled or duplicated by the preprocessing, unlike
+# e.g. parens, braces or semicolons.
+
+
+# Skip preprocessor directives. This breaks the relationship between input and
+# output files, but it makes sorting easy.
+/^#/ d
+
+:start
+
+# Only process data between htop_sigstart and htop_sigend, deleting the rest.
+/htop_sigstart/ {
+   # Skip the start marker itself.
+   # We can't write simply `s/.*htop_sigstart[[:space:]]*//`, because the
+   # initial star is eager, so it would happily consume multiple start
+   # markers. This should never happen, but the script should be robust
+   # just in case.
+   # Solution: Rename the first start marker to a temporary name and
+   # delete using the new name.
+   /htop_delsigstart/ i\
+#error "The sed input contains `htop_sigdelstart`, which is a reserved marker."
+   s/htop_sigstart/htop_delsigstart/
+   s/.*htop_delsigstart[[:space:]]*//
+
+   :loop
+   # Read input until we see the end marker.
+
+   # The end marker has been seen, we can go on with processing.
+   /htop_sigend/ {
+      # We need to save the rest of the line for further processing,
+      # so store the whole line and deal with that later.
+      h
+
+      # Delete the end marker and the rest of the line, keeping just
+      # the signal definition.
+      /htop_sigdelend/ i\
+#error "The sed input contains 'htop_sigdelend', which is a reserved marker."
+      s/htop_sigend/htop_sigdelend/
+      s/htop_sigdelend.*//
+
+      # Normalize spaces to get rid of tabs and newlines and clean
+      # up the output.
+      s/[[:space:]][[:space:]]*/ /g
+      s/^[[:space:]]*//
+      s/[[:space:]]*$//
+
+      # Replace the separator between the signal number and name
+      # with a tab for sorting.
+      s/ htop_sigmid /	/
+      # TODO test whether the above succeeded and report error otherwise.
+
+      # Test whether the signal number is actually a number, as it
+      # would not be sortable otherwise.
+      /^[0-9][0-9]*	/ !i\
+#warning "Encountered non-numeric signal number; sorting may be broken."
+
+      # Print the signal definition.
+      p
+
+      # Process the rest of the line.
+      g
+      s/htop_sigend/htop_sigdelend/
+      s/.*htop_sigdelend//
+      b start
+   }
+
+   :dprep
+   # The end marker was not seen yet, read one more line.
+   N
+   # If the next line is a preprocessor directive, delete it, read
+   # another one and test for preprocessor directives again.
+   s/\n#.*//
+   t dprep
+   # Test for the end marker again.
+   b loop
+}
+
+# The line is outside a range marked as signal definition, suppress it.
+d

signals/PrintSignals.sed

@@ -0,0 +1,9 @@
+# htop - signals/PrintSignals.sed
+# (C) 2023 htop dev team
+# Released under the GNU GPLv2+, see the COPYING file
+# in the source distribution for its full text.
+
+# Single digit, justify name by one space.
+s/^\([0-9]\)	"\(.*\)"$/{ .number=(\1), .name=(" \1 \2") },/
+# Multiple digits or a complex expression, don't justify.
+s/^\(.*\)	"\(.*\)"$/{ .number=(\1), .name=("\1 \2") },/

signals/SignalList.in.c

@@ -0,0 +1,170 @@
+/*
+htop - signals/SignalList.in.c
+(C) 2023 htop dev team
+Released under the GNU GPLv2+, see the COPYING file
+in the source distribution for its full text.
+*/
+
+#include <signal.h>
+
+#define HTOP_SIGENTRY(x) htop_sigstart x htop_sigmid #x htop_sigend
+
+
+HTOP_SIGENTRY(SIGABRT)
+
+HTOP_SIGENTRY(SIGALRM)
+
+HTOP_SIGENTRY(SIGBUS)
+
+/* On Solaris. */
+#ifdef SIGCANCEL
+HTOP_SIGENTRY(SIGCANCEL)
+#endif
+
+#ifdef SIGCHLD
+HTOP_SIGENTRY(SIGCHLD)
+#endif
+
+/* A synonym for SIGCHLD on Linux/MIPS, original name on SysV, omitting
+   if SIGCHLD is also defined, since confusion is unlikely. */
+#ifndef SIGCHLD
+HTOP_SIGENTRY(SIGCLD)
+#endif
+
+HTOP_SIGENTRY(SIGCONT)
+
+/* On BSDs and Alpha, Sparc and MIPS Linuxes. */
+#ifdef SIGEMT
+HTOP_SIGENTRY(SIGEMT)
+#endif
+
+HTOP_SIGENTRY(SIGFPE)
+
+/* On Solaris. */
+#ifdef SIGFREEZE
+HTOP_SIGENTRY(SIGFREEZE)
+#endif
+
+HTOP_SIGENTRY(SIGHUP)
+
+HTOP_SIGENTRY(SIGILL)
+
+/* On Solaris. Also a synonym for SIGPWR on Linux/Alpha. */
+#ifdef SIGINFO
+HTOP_SIGENTRY(SIGINFO)
+#endif
+
+HTOP_SIGENTRY(SIGINT)
+
+HTOP_SIGENTRY(SIGIO)
+
+/* A synonym for SIGABRT on Linux and Solaris, found on OpenBSD and NetBSD,
+ * not on FreeBSD.
+ */
+#ifdef SIGIOT
+HTOP_SIGENTRY(SIGIOT)
+#endif
+
+/* On Solaris. */
+#ifdef SIGJVM1
+HTOP_SIGENTRY(SIGJVM1)
+#endif
+
+/* On Solaris. */
+#ifdef SIGJVM2
+HTOP_SIGENTRY(SIGJVM2)
+#endif
+
+HTOP_SIGENTRY(SIGKILL)
+
+/* On FreeBSD. */
+#ifdef SIGLIBRT
+HTOP_SIGENTRY(SIGLIBRT)
+#endif
+
+/* On Solaris and Linux/SPARC. */
+#ifdef SIGLOST
+HTOP_SIGENTRY(SIGLOST)
+#endif
+
+/* On Solaris. */
+#ifdef SIGLWP
+HTOP_SIGENTRY(SIGLWP)
+#endif
+
+HTOP_SIGENTRY(SIGPIPE)
+
+/* A synonym for SIGIO on Linux and Solaris. */
+#ifdef SIGPOLL
+HTOP_SIGENTRY(SIGPOLL)
+#endif
+
+HTOP_SIGENTRY(SIGPROF)
+
+/* Linux, NetBSD and SysV. */
+#ifdef SIGPWR
+HTOP_SIGENTRY(SIGPWR)
+#endif
+
+HTOP_SIGENTRY(SIGQUIT)
+
+HTOP_SIGENTRY(SIGSEGV)
+
+/* Not on BSDs. */
+#ifdef SIGSTKFLT
+HTOP_SIGENTRY(SIGSTKFLT)
+#endif
+
+HTOP_SIGENTRY(SIGSTOP)
+
+HTOP_SIGENTRY(SIGSYS)
+
+HTOP_SIGENTRY(SIGTERM)
+
+/* On Solaris. */
+#ifdef SIGTHAW
+HTOP_SIGENTRY(SIGTHAW)
+#endif
+
+/* On FreeBSD and OpenBSD. */
+#ifdef SIGTHR
+HTOP_SIGENTRY(SIGTHR)
+#endif
+
+HTOP_SIGENTRY(SIGTRAP)
+
+HTOP_SIGENTRY(SIGTSTP)
+
+HTOP_SIGENTRY(SIGTTIN)
+
+HTOP_SIGENTRY(SIGTTOU)
+
+/* A synonym for SIGSYS on Linux, deprecated.
+#ifdef SIGUNUSED
+HTOP_SIGENTRY(SIGUNUSED)
+#endif
+*/
+
+HTOP_SIGENTRY(SIGURG)
+
+HTOP_SIGENTRY(SIGUSR1)
+
+HTOP_SIGENTRY(SIGUSR2)
+
+HTOP_SIGENTRY(SIGVTALRM)
+
+HTOP_SIGENTRY(SIGXCPU)
+
+HTOP_SIGENTRY(SIGXFSZ)
+
+/* On Solaris. */
+#ifdef SIGXRES
+HTOP_SIGENTRY(SIGXRES)
+#endif
+
+/* On Solaris. */
+#ifdef SIGWAITING
+HTOP_SIGENTRY(SIGWAITING)
+#endif
+
+HTOP_SIGENTRY(SIGWINCH)