More portable handling of loop header files, as done in util-linux

5 files changed, 123 insertions, 12 deletions

diff --git a/Makefile b/Makefile
index a2940b5cc..278887f36 100644
--- a/Makefile
+++ b/Makefile
@@ -42,7 +42,7 @@ DODMALLOC = false
 
 # If you are running a cross compiler, you may want to set this
 # to something more interesting...
-CROSS =
+CROSS = #powerpc-linux-
 CC = $(CROSS)gcc
 STRIPTOOL = $(CROSS)strip
 
@@ -83,12 +83,13 @@ else
     ifeq ($(DOSTATIC),true)
         LDFLAGS += --static
         #
-        #use '-ffunction-sections -fdata-sections' and '--gc-sections' if they work
-        #to try and strip out any unused junk.  Doesn't do much for me, but you may
-        #want to give it a shot...
+        #use '-ffunction-sections -fdata-sections' and '--gc-sections' (if they 
+        # work) to try and strip out any unused junk.  Doesn't do much for me, 
+        # but you may want to give it a shot...
         #
         #ifeq ($(shell $(CC) -ffunction-sections -fdata-sections -S \
-        #       -o /dev/null -xc /dev/null 2>/dev/null && $(LD) --gc-sections -v >/dev/null && echo 1),1)
+        #       -o /dev/null -xc /dev/null 2>/dev/null && $(LD) \
+        #                       --gc-sections -v >/dev/null && echo 1),1)
         #       CFLAGS += -ffunction-sections -fdata-sections
         #       LDFLAGS += --gc-sections
         #endif
@@ -106,7 +107,8 @@ ifdef BB_INIT_SCRIPT
     CFLAGS += -DINIT_SCRIPT='"$(BB_INIT_SCRIPT)"'
 endif
 
-all: busybox busybox.links doc
+
+all: loop.h busybox busybox.links doc
 
 doc: olddoc
 
@@ -154,7 +156,7 @@ docs/busybox/busybox.html: docs/busybox.sgml
 
 
 
-busybox: $(OBJECTS)
+busybox: $(OBJECTS) 
         $(CC) $(LDFLAGS) -o $@ $^ $(LIBRARIES)
         $(STRIP)
 
@@ -164,6 +166,11 @@ busybox.links: busybox.def.h
 nfsmount.o cmdedit.o: %.o: %.h
 $(OBJECTS): %.o: busybox.def.h internal.h  %.c Makefile
 
+utility.o: 
+
+loop.h:
+        @./mk_loop_h.sh
+
 test tests:
         cd tests && $(MAKE) all
 
diff --git a/libbb/mk_loop_h.sh b/libbb/mk_loop_h.sh
new file mode 100755
index 000000000..c33c010ca
--- /dev/null
+++ b/libbb/mk_loop_h.sh
@@ -0,0 +1,34 @@
+#!/bin/sh
+#
+# Figure out (i) the type of dev_t (ii) the defines for loop stuff
+#
+
+rm -f loop.h
+
+# Since 1.3.79 there is an include file <asm/posix_types.h>
+# that defines __kernel_dev_t.
+# (The file itself appeared in 1.3.78, but there it defined __dev_t.)
+# If it exists, we use it, or, rather, <linux/posix_types.h> which
+# avoids namespace pollution.  Otherwise we guess that __kernel_dev_t
+# is an unsigned short (which is true on i386, but false on alpha).
+
+if [ -f /usr/include/linux/posix_types.h ]; then
+   echo '#include <linux/posix_types.h>' >> loop.h
+   echo '#undef dev_t' >> loop.h
+   echo '#define dev_t __kernel_dev_t' >> loop.h
+else
+   echo '#undef dev_t' >> loop.h
+   echo '#define dev_t unsigned short' >> loop.h
+fi
+
+# Next we have to find the loop stuff itself.
+# First try kernel source, then a private version.
+
+if [ -f /usr/include/linux/loop.h ]; then
+   echo '#include <linux/loop.h>' >> loop.h
+else
+   echo '#include "real_loop.h"' >> loop.h
+fi
+
+echo '#undef dev_t' >> loop.h
+
diff --git a/mk_loop_h.sh b/mk_loop_h.sh
new file mode 100755
index 000000000..c33c010ca
--- /dev/null
+++ b/mk_loop_h.sh
@@ -0,0 +1,34 @@
+#!/bin/sh
+#
+# Figure out (i) the type of dev_t (ii) the defines for loop stuff
+#
+
+rm -f loop.h
+
+# Since 1.3.79 there is an include file <asm/posix_types.h>
+# that defines __kernel_dev_t.
+# (The file itself appeared in 1.3.78, but there it defined __dev_t.)
+# If it exists, we use it, or, rather, <linux/posix_types.h> which
+# avoids namespace pollution.  Otherwise we guess that __kernel_dev_t
+# is an unsigned short (which is true on i386, but false on alpha).
+
+if [ -f /usr/include/linux/posix_types.h ]; then
+   echo '#include <linux/posix_types.h>' >> loop.h
+   echo '#undef dev_t' >> loop.h
+   echo '#define dev_t __kernel_dev_t' >> loop.h
+else
+   echo '#undef dev_t' >> loop.h
+   echo '#define dev_t unsigned short' >> loop.h
+fi
+
+# Next we have to find the loop stuff itself.
+# First try kernel source, then a private version.
+
+if [ -f /usr/include/linux/loop.h ]; then
+   echo '#include <linux/loop.h>' >> loop.h
+else
+   echo '#include "real_loop.h"' >> loop.h
+fi
+
+echo '#undef dev_t' >> loop.h
+
diff --git a/real_loop.h b/real_loop.h
new file mode 100644
index 000000000..1bd7fa87a
--- /dev/null
+++ b/real_loop.h
@@ -0,0 +1,37 @@
+/*
+ * include/linux/loop.h
+ *
+ * Written by Theodore Ts'o, 3/29/93.
+ *
+ * Copyright 1993 by Theodore Ts'o.  Redistribution of this file is
+ * permitted under the GNU Public License.
+ */
+
+#define LO_NAME_SIZE    64
+#define LO_KEY_SIZE     32
+       
+struct loop_info {
+        int             lo_number;      /* ioctl r/o */
+        dev_t           lo_device;      /* ioctl r/o */
+        unsigned long   lo_inode;       /* ioctl r/o */
+        dev_t           lo_rdevice;     /* ioctl r/o */
+        int             lo_offset;
+        int             lo_encrypt_type;
+        int             lo_encrypt_key_size;    /* ioctl w/o */
+        int             lo_flags;       /* ioctl r/o */
+        char            lo_name[LO_NAME_SIZE];
+        unsigned char   lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
+        unsigned long   lo_init[2];
+        char            reserved[4];
+};
+
+#define LO_CRYPT_NONE   0
+#define LO_CRYPT_XOR    1
+#define LO_CRYPT_DES    2
+#define LO_CRYPT_IDEA   3
+#define MAX_LO_CRYPT    4
+
+#define LOOP_SET_FD     0x4C00
+#define LOOP_CLR_FD     0x4C01
+#define LOOP_SET_STATUS 0x4C02
+#define LOOP_GET_STATUS 0x4C03
diff --git a/utility.c b/utility.c
index 8c3c5e5fa..719cd98ce 100644
--- a/utility.c
+++ b/utility.c
@@ -53,11 +53,6 @@
 #include <sys/ioctl.h>
 #include <sys/utsname.h>                /* for uname(2) */
 
-#if defined BB_FEATURE_MOUNT_LOOP
-#include <fcntl.h>
-#include <linux/loop.h> /* Pull in loop device support */
-#endif
-
 /* Busybox mount uses either /proc/filesystems or /dev/mtab to get the 
  * list of available filesystems used for the -t auto option */ 
 #if defined BB_FEATURE_USE_PROCFS && defined BB_FEATURE_USE_DEVPS_PATCH
@@ -1459,7 +1454,11 @@ extern int vdprintf(int d, const char *format, va_list ap)
 }
 #endif                                                  /* BB_SYSLOGD */
 
+
 #if defined BB_FEATURE_MOUNT_LOOP
+#include <fcntl.h>
+#include "loop.h" /* Pull in loop device support */
+
 extern int del_loop(const char *device)
 {
         int fd;