man/man-db-2.7.1-zio.dif

---
 config.h.in      |    3 ++
 configure.ac     |   52 +++++++++++++++++++++++++++++++++++++++++
 src/decompress.c |   69 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 123 insertions(+), 1 deletion(-)

--- config.h.in
+++ config.h.in	2024-10-18 12:05:43.927063826 +0000
@@ -1148,6 +1148,9 @@
 /* Define to 1 if you have the `z' library (-lz). */
 #undef HAVE_LIBZ
 
+/* Define to 1 if you have libzio for opening compressed manuals */
+#undef HAVE_ZIO
+
 /* Define to 1 if the bcrypt library is guaranteed to be present. */
 #undef HAVE_LIB_BCRYPT
 
--- configure.ac
+++ configure.ac	2024-10-18 12:05:43.927063826 +0000
@@ -35,6 +35,18 @@ MAN_ARG_DEVICE
 MAN_ARG_DB
 MAN_ARG_CONFIG_FILE
 MAN_ARG_SECTIONS
+AC_ARG_WITH([zio],
+[AS_HELP_STRING([--with-zio=LIBRARY], [use zlib/libbz2 wrapper library LIBRARY (libzio)])],
+	[if test -z "$withval" -o "$withval" = "yes"
+	 then
+		zio=libzio
+	 elif test "$withval" = "no"
+	 then
+		AC_MSG_ERROR(--with-zio requires an argument)
+	 else
+		zio=$withval
+	 fi],
+	[: ${zio=no}])
 MAN_ARG_AUTOMATIC_CREATE
 MAN_ARG_AUTOMATIC_UPDATE
 MAN_ARG_CATS
@@ -374,6 +386,46 @@ AC_DEFINE_UNQUOTED([PROG_UNXZ], ["$unxz"
 AC_DEFINE_UNQUOTED([PROG_UNLZIP], ["$unlzip"], [Program to use as unlzip.])
 AC_DEFINE_UNQUOTED([PROG_UNZSTD], ["$unzstd"], [Program to use as unzstd.])
 MAN_COMPRESS_LIB([z], [gzopen])
+dnl Check for zlib and libbz2 libraries to use this together
+dnl with SUSE's libzio to open compressed info files.
+dnl
+if test "$zio" = "no" || test -n "$zio"
+then
+    AC_CHECK_HEADER(zio.h,[
+      for lib in ${zio#lib} zio
+      do
+	AC_CHECK_LIB($lib, fzopen,              [LIBS="-l$lib $LIBS"; am_cv_libzio=yes])
+      done
+    ])
+    if test "$am_cv_libzio" = yes; then
+      AC_DEFINE([COMP_SRC],[],[Define if you have compressors and want to support compressed cat files.])
+      AC_DEFINE([HAVE_ZIO],[],[Define to 1 if you have libzio for opening compressed manuals])
+      AC_CHECK_HEADER(zlib.h,[
+	for lib in z gz
+	do
+	  AC_CHECK_LIB($lib, gzopen,             [LIBS="$LIBS -Wl,--no-as-needed -l$lib"; break])
+	done
+      ])
+      AC_CHECK_HEADER(bzlib.h,[
+	for lib in bz2 bzip2
+	do
+	  AC_CHECK_LIB($lib, BZ2_bzopen,         [LIBS="$LIBS -Wl,--no-as-needed -l$lib"; break])
+	done
+      ])
+      AC_CHECK_HEADER(lzmadec.h, [
+	for lib in lzma lzmadec
+	do
+	  AC_CHECK_LIB($lib, lzmadec_open,       [LIBS="$LIBS -Wl,--no-as-needed -l$lib"; break])
+	done
+      ])
+      AC_CHECK_HEADER(lzma.h, [
+	for lib in lzma
+	do
+	  AC_CHECK_LIB($lib, lzma_easy_encoder,  [LIBS="$LIBS -Wl,--no-as-needed -l$lib"; break])
+	done
+      ])
+    fi
+fi
 dnl To add more decompressors just follow the scheme above.
 
 # Check for various header files and associated libraries.
--- src/decompress.c
+++ src/decompress.c	2024-10-18 12:11:37.516631374 +0000
@@ -40,12 +40,17 @@
 
 #include "pipeline.h"
 
+#include "appendstr.h"
 #include "attribute.h"
 #include "minmax.h"
 #include "xalloc.h"
 #include "xstrndup.h"
 #include "xvasprintf.h"
 
+#ifdef HAVE_ZIO
+#  include "zio.h"
+#endif /* HAVE_ZIO */
+
 #include "manconfig.h"
 
 #include "compression.h"
@@ -189,6 +194,32 @@ static decompress *decompress_try_zlib (
 #  define OPEN_FLAGS_UNUSED MAYBE_UNUSED
 #endif /* HAVE_LIBZ */
 
+#ifdef HAVE_ZIO
+
+static void decompress_zio (void *data)
+{
+	const char *what = (const char*)data;
+	FILE *file;
+
+	file = fdzopen(dup (fileno (stdin)), "r", what);
+	if (!file)
+		return;
+
+	for (;;) {
+		char buffer[4096];
+		int r = fread(buffer, sizeof(char), sizeof(buffer), file);
+		if (r <= 0)
+			break;
+		if (fwrite (buffer, 1, (size_t) r, stdout) < (size_t) r)
+			break;
+	}
+
+	fclose(file);
+	return;
+}
+
+#endif /* HAVE_ZIO */
+
 decompress *decompress_open (const char *filename, int flags OPEN_FLAGS_UNUSED)
 {
 	pipecmd *cmd;
@@ -203,6 +234,38 @@ decompress *decompress_open (const char
 	if (stat (filename, &st) < 0 || S_ISDIR (st.st_mode))
 		return NULL;
 
+#ifdef HAVE_ZIO
+	ext = strrchr (filename, '.');
+	if (ext) {
+		const char *opt;
+		char *name = NULL;
+
+		if (STREQ (ext, ".gz"))
+			opt = "g";
+		else if (STREQ (ext, ".z"))
+			opt = "z";
+		else if (STREQ (ext, ".bz2"))
+			opt = "b";
+		else if (STREQ (ext, ".xz"))
+			opt = "x";
+		else if (STREQ (ext, ".lzma"))
+			opt = "l";
+		else if (STREQ (ext, ".Z"))
+			opt = "Z";
+		else
+			goto nozio;
+
+		/* informational only; no shell quoting concerns */
+		name = appendstr (NULL, "libzio < ", filename, (void *) 0);
+		cmd = pipecmd_new_function (name, &decompress_zio, NULL,
+					    (void *)opt);
+		pipecmd_pre_exec (cmd, sandbox_load, sandbox_free, sandbox);
+		p = pipeline_new_commands (cmd, (void *) 0);
+		free (name);
+		goto got_pipeline;
+	}
+#endif /* HAVE_ZIO */
+
 #ifdef HAVE_LIBZ
 	filename_len = strlen (filename);
 	if (filename_len > 3 && STREQ (filename + filename_len - 3, ".gz")) {
@@ -220,7 +283,11 @@ decompress *decompress_open (const char
 	}
 #endif /* HAVE_LIBZ */
 
+#ifdef HAVE_ZIO
+nozio:
+#else
 	ext = strrchr (filename, '.');
+#endif /* HAVE_LIBZ */
 	if (ext) {
 		++ext;
 
@@ -313,7 +380,7 @@ void decompress_inprocess_replace (decom
 
 void decompress_start (decompress *d)
 {
-	if (d->tag == DECOMPRESS_PIPELINE)
+	if (d && d->tag == DECOMPRESS_PIPELINE)
 		pipeline_start (d->u.p);
 }