Version 0.0.1997.03.27

13 files changed, 101 insertions, 23 deletions

diff --git a/Makefile b/Makefile
index aa0976a..0278488 100644
--- a/Makefile
+++ b/Makefile
@@ -7,10 +7,11 @@ all:
 	@echo
 
 clean:
-	make -C src clean
-	make -C test clean
+	make -C src/libtrace clean
+	make -C src/ltrace clean
+	make -C src/test clean
 	rm -f *.o
 
 dist:
 	make clean
-	( cd .. ; tar zcvf libtrace-`date +%y%m%d`.tgz libtrace )
+	( cd .. ; tar zcvf ltrace-`date +%y%m%d`.tgz ltrace )
diff --git a/lib/libtrace.so.1 b/lib/libtrace.so.1
new file mode 100755
index 0000000..e4b03b0
--- /dev/null
+++ b/lib/libtrace.so.1
diff --git a/src/init_libtrace.c b/src/init_libtrace.c
deleted file mode 100644
index 4955791..0000000
--- a/src/init_libtrace.c
+++ /dev/null
@@ -1,6 +0,0 @@
-#include <hck/syscall.h>
-
-void init_libtrace(void)
-{
-	_sys_write(1,"Hola\n",5);
-}
diff --git a/src/Makefile b/src/libtrace/Makefile
index 71bf97c..cee9a61 100644
--- a/src/Makefile
+++ b/src/libtrace/Makefile
@@ -1,5 +1,6 @@
+TOPDIR	=	/home/cespedes/c/ltrace
 CC	=	gcc
-CFLAGS	=	-Wall -O2 -I../include
+CFLAGS	=	-Wall -O2 -I$(TOPDIR)/include
 LD	=	ld
 
 OBJS	=	__setfpucw.o init_libtrace.o
@@ -8,6 +9,7 @@ all:		libtrace.so.1
 
 libtrace.so.1:	$(OBJS)
 		$(LD) -shared -m elf_i386 -soname $@ -o $@ $(OBJS)
+		cp libtrace.so.1 $(TOPDIR)/lib
 
 clean:
 		rm -f $(OBJS) libtrace.so.1
diff --git a/src/__setfpucw.c b/src/libtrace/__setfpucw.c
index 5b48c37..5b48c37 100644
--- a/src/__setfpucw.c
+++ b/src/libtrace/__setfpucw.c
diff --git a/src/libtrace/init_libtrace.c b/src/libtrace/init_libtrace.c
new file mode 100644
index 0000000..fb53721
--- /dev/null
+++ b/src/libtrace/init_libtrace.c
@@ -0,0 +1,68 @@
+#include <linux/elf.h>
+#include <hck/syscall.h>
+
+static int errno;
+
+void init_libtrace(void)
+{
+	unsigned long tmp[0];
+	unsigned long *stack = tmp;
+	int phnum=0, phent=0;
+	struct elf_phdr * phdr = NULL;
+	int i;
+	struct dynamic * dpnt;
+	struct elf32_sym * symtab = NULL;
+	void * strtab = NULL;
+
+/*
+ * When loading the interpreter, in linux/fs/binfmt_elf.h, the stack
+ * is filled with an auxiliary table defined in include/linux/elf.h;
+ * it has some important things such as pointers to the program
+ * headers.  We are trying to find that table.
+ *
+ */
+	for(; (stack < (unsigned long *)(0xc0000000-256)); stack++) {
+		if ((stack[0]==3) && (stack[2]==4) && (stack[4]==5) && (stack[6]==6)) {
+			phdr = (struct elf_phdr *)stack[1];
+			phent = stack[3];
+			phnum = stack[5];
+			break;
+		}
+	}
+	if (!phdr) {
+		_sys_write(2,"No auxiliary table in stack?\n",29);
+		return;
+	}
+
+	for(i=0; i<phnum; i++) {
+		if (phdr->p_type == PT_DYNAMIC) {
+			break;
+		}
+		phdr = (struct elf_phdr *)((void*)phdr + phent);
+	}
+	if (!phdr || phdr->p_type != PT_DYNAMIC) {
+		_sys_write(2,"No .dynamic in file?\n",21);
+		return;
+	}
+	dpnt = (struct dynamic *)phdr->p_vaddr;
+
+	while(dpnt->d_tag) {
+		if (dpnt->d_tag == DT_SYMTAB) {
+			symtab = (struct elf32_sym *) dpnt->d_un.d_ptr;
+		}
+		if (dpnt->d_tag == DT_STRTAB) {
+			strtab = (void *) dpnt->d_un.d_ptr;
+		}
+		dpnt++;
+	}
+	if (!symtab) {
+		_sys_write(2, "No .symtab?\n",12);
+		return;
+	}
+	if (!strtab) {
+		_sys_write(2, "No .strtab?\n",12);
+		return;
+	}
+
+	_sys_write(2,"Hola\n",5);
+}
diff --git a/src/ltrace/Makefile b/src/ltrace/Makefile
new file mode 100644
index 0000000..596a48d
--- /dev/null
+++ b/src/ltrace/Makefile
@@ -0,0 +1,11 @@
+TOPDIR	=	/home/cespedes/c/ltrace
+CC	=	gcc
+CFLAGS	=	-Wall -O2 -I$(TOPDIR)/include -DTOPDIR=\"$(TOPDIR)\"
+LD	=	ld
+
+OBJS	=	ltrace.o
+
+all:		ltrace
+
+clean:
+		rm -f $(OBJS) ltrace
diff --git a/src/ltrace/ltrace.c b/src/ltrace/ltrace.c
new file mode 100644
index 0000000..d511ba9
--- /dev/null
+++ b/src/ltrace/ltrace.c
@@ -0,0 +1,15 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+int main(int argc, char **argv)
+{
+	if (argc<2) {
+		fprintf(stderr, "Usage: %s <program> [<arguments>]\n", argv[0]);
+		exit(1);
+	}
+	setenv("LD_PRELOAD", TOPDIR "/lib/libtrace.so.1", 1);
+	execve(argv[1], &argv[1], environ);
+	fprintf(stderr, "Couldn't execute %s\n", argv[1]);
+	exit(1);
+}
diff --git a/test/Makefile b/src/test/Makefile
index 482875a..482875a 100644
--- a/test/Makefile
+++ b/src/test/Makefile
diff --git a/test/hacks.c b/src/test/hacks.c
index 43e7696..43e7696 100644
--- a/test/hacks.c
+++ b/src/test/hacks.c
diff --git a/test/test.c b/src/test/test.c
index ec22a9d..ec22a9d 100644
--- a/test/test.c
+++ b/src/test/test.c
diff --git a/test/test2 b/test/test2
deleted file mode 100755
index 90c5cfc..0000000
--- a/test/test2
+++ /dev/null
diff --git a/test/test2.c b/test/test2.c
deleted file mode 100644
index 988bf6c..0000000
--- a/test/test2.c
+++ /dev/null
@@ -1,13 +0,0 @@
-void function(i)
-{
-	int * sp;
-
-	sp = &i;
-
-	printf("%d\n", sp[0]);
-}
-
-main()
-{
-	function(23);
-}