More ELF loader changes

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5261 42af7a65-404d-4744-a932-0658087f49c3

examples/README.txt

@@ -297,6 +297,53 @@ examples/discover
     CONFIG_EXAMPLES_DISCOVER_DRIPADDR - Router IP address
     CONFIG_EXAMPLES_DISCOVER_NETMASK - Network Mask
 
+examples/elf
+^^^^^^^^^^^^
+
+  This example builds a small ELF loader test case.  This includes several
+  test programs under examples/elf tests.  These tests are build using
+  the relocatable ELF format and installed in a ROMFS file system.  At run time,
+  each program in the ROMFS file system is executed.  Requires CONFIG_ELF.
+  Other configuration options:
+
+    CONFIG_EXAMPLES_ELF_DEVMINOR - The minor device number of the ROMFS block.
+      For example, the N in /dev/ramN. Used for registering the RAM block driver
+      that will hold the ROMFS file system containing the ELF executables to be
+      tested.  Default: 0
+
+    CONFIG_EXAMPLES_ELF_DEVPATH - The path to the ROMFS block driver device.  This
+      must match EXAMPLES_ELF_DEVMINOR. Used for registering the RAM block driver
+      that will hold the ROMFS file system containing the ELF executables to be
+      tested.  Default: "/dev/ram0"
+
+  NOTES:
+
+  1. Your top-level nuttx/Make.defs file must include an approproate definition,
+     LDELFFLAGS, to generate a relocatable ELF object.  With GNU LD, this should
+     include '-r' and '-e main' (or _main on some platforms).
+
+       LDELFFLAGS = -r -e main
+
+     If you use GCC to link, you make also need to include '-nostdlib' or 
+     '-nostartfiles' and '-nodefaultlibs'.
+
+  2. This example also requires genromfs.  genromfs can be build as part of the
+     nuttx toolchain.  Or can built from the genromfs sources that can be found
+     at misc/tools/genromfs-0.5.2.tar.gz.  In any event, the PATH variable must
+     include the path to the genromfs executable.
+
+  3. ELF size:  The ELF files in this example are, be default, quite large
+     because they include a lot of "build garbage".  You can greately reduce the
+     size of the ELF binaries are using the objcopy --strip-unneeded command to
+     remove un-necessary information from the ELF files.
+
+  4. Simulator.  You cannot use this example with the the NuttX simulator on
+     Cygwin.  That is because the Cygwin GCC does not generate ELF file but
+     rather some Windows-native binary format.
+
+     If you really want to do this, you can create a NuttX x86 buildroot toolchain
+     and use that be build the ELF executables for the ROMFS file system.
+
 examples/ftpc
 ^^^^^^^^^^^^^
 

examples/elf/Kconfig

@@ -10,4 +10,20 @@ config EXAMPLES_ELF
 		Enable the ELF loader example
 
 if EXAMPLES_ELF
+config EXAMPLES_ELF_DEVMINOR
+	int "ROMFS Minor Device Number"
+	default 0
+	---help---
+		The minor device number of the ROMFS block. For example, the N in /dev/ramN.
+		Used for registering the RAM block driver that will hold the ROMFS file system
+		containing the ELF executables to be tested.  Default: 0
+
+config EXAMPLES_ELF_DEVPATH
+	string "ROMFS Devie Path"
+	default "/dev/ram0"
+	---help---
+		The path to the ROMFS block driver device.  This must match EXAMPLES_ELF_DEVMINOR.
+		Used for registering the RAM block driver that will hold the ROMFS file system
+		containing the ELF executables to be tested.  Default: "/dev/ram0"
+
 endif

examples/elf/Makefile

@@ -61,7 +61,7 @@ ROOTDEPPATH	= --dep-path .
 VPATH		= 
 
 all: .built
-.PHONY: headers clean depend disclean
+.PHONY: headers clean_tests clean depend disclean
 
 $(AOBJS): %$(OBJEXT): %.S
 	$(call ASSEMBLE, $<, $@)
@@ -72,7 +72,7 @@ $(COBJS): %$(OBJEXT): %.c
 headers:
 	@$(MAKE) -C tests TOPDIR="$(TOPDIR)" APPDIR="$(APPDIR)" CROSSDEV=$(CROSSDEV)
 
-.built: $(OBJS)
+.built: headers $(OBJS)
 	@( for obj in $(OBJS) ; do \
 		$(call ARCHIVE, $(BIN), $${obj}); \
 	done ; )
@@ -88,7 +88,10 @@ context:
 
 depend: .depend
 
-clean:
+clean_tests:
+	@$(MAKE) -C tests TOPDIR="$(TOPDIR)" APPDIR="$(APPDIR)" CROSSDEV=$(CROSSDEV) clean
+
+clean: clean_tests
 	@rm -f *.o *~ .*.swp .built
 	$(call CLEAN)
 

examples/elf/elf_main.c

@@ -89,9 +89,16 @@
 
 #define SECTORSIZE   512
 #define NSECTORS(b)  (((b)+SECTORSIZE-1)/SECTORSIZE)
-#define ROMFSDEV     "/dev/ram0"
 #define MOUNTPT      "/mnt/romfs"
 
+#ifndef CONFIG_EXAMPLES_ELF_DEVMINOR
+#  define CONFIG_EXAMPLES_ELF_DEVMINOR 0
+#endif
+
+#ifndef CONFIG_EXAMPLES_ELF_DEVPATH
+#  define CONFIG_EXAMPLES_ELF_DEVPATH "/dev/ram0"
+#endif
+
 /* If CONFIG_DEBUG is enabled, use dbg instead of printf so that the
  * output will be synchronous with the debug output.
  */
@@ -166,8 +173,9 @@ int elf_main(int argc, char *argv[])
 
   /* Create a ROM disk for the ROMFS filesystem */
 
-  message("Registering romdisk\n");
-  ret = romdisk_register(0, romfs_img, NSECTORS(romfs_img_len), SECTORSIZE);
+  message("Registering romdisk at /dev/ram%d\n", CONFIG_EXAMPLES_ELF_DEVMINOR);
+  ret = romdisk_register(CONFIG_EXAMPLES_ELF_DEVMINOR, romfs_img,
+                         NSECTORS(romfs_img_len), SECTORSIZE);
   if (ret < 0)
     {
       err("ERROR: romdisk_register failed: %d\n", ret);
@@ -178,13 +186,13 @@ int elf_main(int argc, char *argv[])
   /* Mount the file system */
 
   message("Mounting ROMFS filesystem at target=%s with source=%s\n",
-         MOUNTPT, ROMFSDEV);
+         MOUNTPT, CONFIG_EXAMPLES_ELF_DEVPATH);
 
-  ret = mount(ROMFSDEV, MOUNTPT, "romfs", MS_RDONLY, NULL);
+  ret = mount(CONFIG_EXAMPLES_ELF_DEVPATH, MOUNTPT, "romfs", MS_RDONLY, NULL);
   if (ret < 0)
     {
       err("ERROR: mount(%s,%s,romfs) failed: %s\n",
-              ROMFSDEV, MOUNTPT, errno);
+              CONFIG_EXAMPLES_ELF_DEVPATH, MOUNTPT, errno);
       elf_uninitialize();
     }
 
@@ -219,6 +227,6 @@ int elf_main(int argc, char *argv[])
       sleep(4);
     }
 
-  message("End-of-Test.. Exit-ing\n");
+  message("End-of-Test.. Exiting\n");
   return 0;
 }

examples/elf/tests/errno/Makefile

@@ -39,7 +39,7 @@
 BIN = errno
 
 SRCS = $(BIN).c
-OBJS = $(BIN:.c=.o)
+OBJS = $(SRCS:.c=.o)
 
 all: $(BIN)
 

examples/elf/tests/hello++/Makefile

@@ -64,7 +64,7 @@ all: $(BIN1) $(BIN2) $(BIN3) $(BIN4)
 
 $(OBJS): %.o: %.cpp
 	@echo "CC: $<"
-	@$(CXX) -c $(CXXPICFLAGS) $< -o $@
+	@$(CXX) -c $(CXXFLAGS) $< -o $@
 
 # This contains libstdc++ stubs to that you can build C++ code
 # without actually having libstdc++

examples/elf/tests/hello/Makefile

@@ -39,7 +39,7 @@
 BIN = hello
 
 SRCS = $(BIN).c
-OBJS = $(BIN:.c=.o)
+OBJS = $(SRCS:.c=.o)
 
 all: $(BIN)
 

examples/elf/tests/longjmp/Makefile

@@ -39,7 +39,7 @@
 BIN = longjmp
 
 SRCS = $(BIN).c
-OBJS = $(BIN:.c=.o)
+OBJS = $(SRCS:.c=.o)
 
 all: $(BIN)
 

examples/elf/tests/mutex/Makefile

@@ -39,7 +39,7 @@
 BIN = mutex
 
 SRCS = $(BIN).c
-OBJS = $(BIN:.c=.o)
+OBJS = $(SRCS:.c=.o)
 
 all: $(BIN)
 

examples/elf/tests/pthread/Makefile

@@ -39,7 +39,7 @@
 BIN = pthread
 
 SRCS = $(BIN).c
-OBJS = $(BIN:.c=.o)
+OBJS = $(SRCS:.c=.o)
 
 all: $(BIN)
 

examples/elf/tests/signal/Makefile

@@ -39,7 +39,7 @@
 BIN = signal
 
 SRCS = $(BIN).c
-OBJS = $(BIN:.c=.o)
+OBJS = $(SRCS:.c=.o)
 
 all: $(BIN)
 

examples/elf/tests/struct/Makefile

@@ -38,7 +38,7 @@
 
 CFLAGS += -I.
 
-BIN = struct
+BIN  = struct
 SRCS = struct_main.c struct_dummy.c
 OBJS = $(SRCS:.c=.o)
 

examples/elf/tests/task/Makefile

@@ -39,7 +39,7 @@
 BIN = task
 
 SRCS = $(BIN).c
-OBJS = $(BIN:.c=.o)
+OBJS = $(SRCS:.c=.o)
 
 all: $(BIN)