initial preload filetrace

Author: colinthomas-z80

devel/Makefile

@@ -0,0 +1 @@
+../.module.mk

devel/filetrace/.gitignore

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+filetrace_ld.so

devel/filetrace/Makefile

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+SOURCES = \
+	  filetrace_ld.c
+
+include ../../config.mk
+include ../../rules.mk
+
+LOCAL_LINKAGE = ../../dttools/src/libdttools.a
+
+LIBRARIES = filetrace_ld.$(CCTOOLS_DYNAMIC_SUFFIX)
+OBJECTS = filetrace_ld.o
+
+TARGETS = $(LIBRARIES)
+
+filetrace_ld.so: filetrace_ld.c
+	$(CCTOOLS_CC) -shared -fPIC filetrace_ld.c $(CCTOOLS_INTERNAL_CCFLAGS) -ldl $(CCTOOLS_INTERNAL_LDFLAGS) $(LOCAL_LINKAGE) $(CCTOOLS_EXTERNAL_LINKAGE) -o filetrace_ld.so
+
+all: $(TARGETS)
+
+.PHONY: all

devel/filetrace/filetrace_ld.c

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+#include <stdio.h>
+#include <stdlib.h>
+#include <dlfcn.h>
+#include <string.h>
+
+#include "itable.h"
+
+typedef FILE *(*fopen_t)(const char *p, const char *m);
+typedef int (*open_t)(const char *p, int f);
+typedef ssize_t(*rw_t)(int fd, void *b, ssize_t c);
+typedef int (*stat_t)(const char *p, void *s);
+typedef int (*fstat_t)(int fd, void *s);
+
+typedef struct {
+	char *pathname;
+	int num_open;
+	int bytes_read;
+	int bytes_write;
+	int num_reads;
+	int num_writes;
+	int num_stat;
+} table_entry;
+
+
+struct itable *file_table; /* maps fd -> table_entry */
+
+void print_file_table(struct itable *t);
+
+void __attribute__((constructor)) filetrace_init() {
+	file_table = itable_create(0);
+}
+
+void __attribute__((destructor)) filetrace_exit() {
+	print_file_table(file_table);
+	itable_clear(file_table, 0);
+	itable_delete(file_table);
+}
+
+void file_table_event_open(int fd, const char *pathname, int flags) {
+	if(!itable_lookup(file_table, fd)){
+		table_entry *e = malloc(sizeof(table_entry));
+		e->num_open = 1;
+		e->pathname = strdup(pathname); 
+		itable_insert(file_table, fd, e);
+	} else {
+		table_entry *e = itable_lookup(file_table, fd);
+		e->num_open += 1;
+	}
+}
+
+FILE *fopen(const char *pathname, const char *mode) {
+	fopen_t real_fopen = dlsym(RTLD_NEXT, "fopen");
+	return real_fopen(pathname,mode);
+}
+
+int open(const char *pathname, int flags) {
+	open_t real_open = dlsym(RTLD_NEXT, "open");
+	int fd = real_open(pathname,flags);
+	file_table_event_open(fd, pathname, flags);
+	return fd;
+}
+
+ssize_t read(int fd, void *buf, size_t count){
+	rw_t real_read = dlsym(RTLD_NEXT, "read");
+	return real_read(fd, buf, count);
+}
+
+ssize_t write(int fd, void *buf, size_t count){
+	rw_t real_write = dlsym(RTLD_NEXT, "write");
+	return real_write(fd, buf, count);
+}
+
+int stat(const char *pathname, void *statbuf){
+	stat_t real_stat = dlsym(RTLD_NEXT, "stat");
+	return real_stat(pathname, statbuf);
+}
+
+int fstat(int fd, void *statbuf){
+	fstat_t real_fstat = dlsym(RTLD_NEXT, "fstat");
+	return real_fstat(fd, statbuf);
+}
+
+void print_file_table(struct itable *t){
+	printf("Filetrace Summary\n");
+	
+	uint64_t fd;
+	table_entry *e;
+	ITABLE_ITERATE(t, fd, e){
+		printf("File Descriptor: %d\n", fd);
+		printf("\tpathname: %s\n", e->pathname);
+		printf("\tnum_open: %d\n\n", e->num_open);
+	}
+}