diff --git a/tools/lsd/Android.mk b/tools/lsd/Android.mk
new file mode 100644
index 0000000..a224741
--- /dev/null
+++ b/tools/lsd/Android.mk
@@ -0,0 +1,43 @@
+# Copyright 2005 The Android Open Source Project
+#
+# Android.mk for lsd 
+#
+
+LOCAL_PATH:= $(call my-dir)
+
+ifeq ($(TARGET_ARCH),arm)
+include $(CLEAR_VARS)
+
+LOCAL_LDLIBS += -ldl
+LOCAL_CFLAGS += -O2 -g 
+LOCAL_CFLAGS += -fno-function-sections -fno-data-sections -fno-inline 
+LOCAL_CFLAGS += -Wall -Wno-unused-function #-Werror
+LOCAL_CFLAGS += -DBIG_ENDIAN=1
+LOCAL_CFLAGS += -DARM_SPECIFIC_HACKS
+LOCAL_CFLAGS += -DSUPPORT_ANDROID_PRELINK_TAGS
+LOCAL_CFLAGS += -DDEBUG
+
+ifeq ($(HOST_OS),windows)
+LOCAL_LDLIBS += -lintl
+endif
+
+LOCAL_SRC_FILES := \
+        cmdline.c \
+        debug.c \
+        hash.c \
+        lsd.c \
+        main.c
+
+LOCAL_C_INCLUDES:= \
+	$(LOCAL_PATH)/ \
+	external/elfutils/lib/ \
+	external/elfutils/libelf/ \
+	external/elfutils/libebl/
+
+LOCAL_STATIC_LIBRARIES := libelf libebl libebl_arm #dl
+
+LOCAL_MODULE := lsd
+
+include $(BUILD_HOST_EXECUTABLE)
+endif #TARGET_ARCH==arm
+
diff --git a/tools/lsd/cmdline.c b/tools/lsd/cmdline.c
new file mode 100644
index 0000000..a3445cd
--- /dev/null
+++ b/tools/lsd/cmdline.c
@@ -0,0 +1,130 @@
+#include <debug.h>
+#include <cmdline.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <string.h>
+#include <ctype.h>
+
+extern char *optarg;
+extern int optind, opterr, optopt;
+
+static struct option long_options[] = {
+	{"verbose", no_argument, 0, 'V'},
+	{"help", no_argument, 0, 'h'},
+	{"print-info", no_argument, 0, 'p'},
+	{"list-needed-libs", no_argument, 0, 'n'},
+	{"lookup",     required_argument, 0, 'L'},
+	{0, 0, 0, 0},
+};
+
+/* This array must parallel long_options[] */
+static const char *descriptions[] = {
+	"print verbose output",
+	"print help screen",
+	"for each file, generate a listing of all dependencies that each symbol "
+	     "satisfies",
+	"print out a list of needed libraries",
+	"provide a directory for library lookup"
+};
+
+void print_help(void)
+{
+    fprintf(stdout, 
+			"invokation:\n"
+			"\tlsd file1 [file2 file3 ... fileN] [-Ldir1 -Ldir2 ... -LdirN] "
+			"[-Vpn]\n"
+			"or\n"
+			"\tlsd -h\n\n");
+	fprintf(stdout, "options:\n");
+	struct option *opt = long_options;
+	const char **desc = descriptions;
+	while (opt->name) {
+		fprintf(stdout, "\t-%c\n"
+						"\t--%-15s: %s\n",
+				opt->val,
+				opt->name,
+				*desc);
+		opt++;
+		desc++;
+	}
+}
+
+int get_options(int argc, char **argv,
+				int *list_needed_libs,
+				int *info,
+                char ***dirs,
+                int *num_dirs,
+                int *verbose)
+{
+    int c;
+
+	ASSERT(list_needed_libs);
+	*list_needed_libs = 0;
+	ASSERT(info);
+	*info = 0;
+    ASSERT(verbose);
+    *verbose = 0;
+    ASSERT(dirs);
+	*dirs = NULL;
+    ASSERT(num_dirs);
+    int size = 0;
+    *num_dirs = 0;
+
+    while (1) {
+        /* getopt_long stores the option index here. */
+        int option_index = 0;
+
+        c = getopt_long (argc, argv, 
+                         "VhpnL:",
+                         long_options, 
+                         &option_index);
+        /* Detect the end of the options. */
+        if (c == -1) break;
+
+        if (isgraph(c)) {
+            INFO ("option -%c with value `%s'\n", c, (optarg ?: "(null)"));
+        }
+
+#define SET_STRING_OPTION(name) do { \
+    ASSERT(optarg);                  \
+    (*name) = strdup(optarg);        \
+} while(0)
+
+        switch (c) {
+        case 0:
+            /* If this option set a flag, do nothing else now. */
+            if (long_options[option_index].flag != 0)
+                break;
+            INFO ("option %s", long_options[option_index].name);
+            if (optarg)
+                INFO (" with arg %s", optarg);
+            INFO ("\n");
+            break;
+        case 'h': print_help(); exit(1); break;
+		case 'V': *verbose = 1; break;
+		case 'p': *info = 1; break;
+		case 'n': *list_needed_libs = 1; break;
+        case 'L': 
+            {
+                if (*num_dirs == size) {
+                    size += 10;
+                    *dirs = (char **)REALLOC(*dirs, size * sizeof(char *));
+                }
+                SET_STRING_OPTION(((*dirs) + *num_dirs));
+                (*num_dirs)++;
+            }
+			break;
+        case '?':
+            /* getopt_long already printed an error message. */
+            break;
+
+#undef SET_STRING_OPTION
+
+        default:
+            FAILIF(1, "Unknown option");
+        }
+    }
+
+    return optind;
+}
diff --git a/tools/lsd/cmdline.h b/tools/lsd/cmdline.h
new file mode 100644
index 0000000..fc3be3e
--- /dev/null
+++ b/tools/lsd/cmdline.h
@@ -0,0 +1,13 @@
+#ifndef CMDLINE_H
+#define CMDLINE_H
+
+void print_help(void);
+
+int get_options(int argc, char **argv,
+				int *list_needed_libs,
+				int *info,
+                char ***dirs,
+                int *num_dirs,
+                int *verbose);
+
+#endif/*CMDLINE_H*/
diff --git a/tools/lsd/common.h b/tools/lsd/common.h
new file mode 100644
index 0000000..6447b10
--- /dev/null
+++ b/tools/lsd/common.h
@@ -0,0 +1,12 @@
+#ifndef COMMON_H
+#define COMMON_H
+
+#include <libelf.h>
+#include <elf.h>
+
+#define unlikely(expr) __builtin_expect (expr, 0)
+#define likely(expr)   __builtin_expect (expr, 1)
+
+#define MIN(a,b) ((a)<(b)?(a):(b)) /* no side effects in arguments allowed! */
+
+#endif/*COMMON_H*/
diff --git a/tools/lsd/debug.c b/tools/lsd/debug.c
new file mode 100644
index 0000000..54b18df
--- /dev/null
+++ b/tools/lsd/debug.c
@@ -0,0 +1,39 @@
+#include <debug.h>
+#include <stdio.h>
+#include <ctype.h>
+
+#define NUM_COLS  (32)
+
+int dump_hex_buffer(FILE *s, void *b, size_t len, size_t elsize)
+{
+    int num_nonprintable = 0;
+    int i, last;
+    char *pchr = (char *)b;
+    fputc('\n', s);
+    for (i = last = 0; i < len; i++) {
+        if (!elsize) {
+            if (i && !(i % 4)) fprintf(s, " ");
+            if (i && !(i % 8)) fprintf(s, " ");
+        }
+        else {
+            if (i && !(i % elsize)) fprintf(s, " ");
+        }
+
+        if (i && !(i % NUM_COLS)) {
+            while (last < i) {
+                if (isprint(pchr[last]))
+                    fputc(pchr[last], s); 
+                else {
+                    fputc('.', s); 
+                    num_nonprintable++;
+                }
+                last++;
+            }
+            fprintf(s, " (%d)\n", i);
+        }
+        fprintf(s, "%02x", (unsigned char)pchr[i]);
+    }
+    if (i && (i % NUM_COLS)) fputs("\n", s);
+    return num_nonprintable;
+}
+
diff --git a/tools/lsd/debug.h b/tools/lsd/debug.h
new file mode 100644
index 0000000..f7842f8
--- /dev/null
+++ b/tools/lsd/debug.h
@@ -0,0 +1,93 @@
+#ifndef DEBUG_H
+#define DEBUG_H
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <common.h>
+
+#ifdef DEBUG
+
+#define FAILIF(cond, msg...) do {                        \
+	if (unlikely(cond)) {                                \
+        fprintf(stderr, "%s(%d): ", __FILE__, __LINE__); \
+		fprintf(stderr, ##msg);                          \
+		exit(1);                                         \
+	}                                                    \
+} while(0)
+
+/* Debug enabled */
+#define ASSERT(x) do {                                \
+	if (unlikely(!(x))) {                             \
+		fprintf(stderr,                               \
+				"ASSERTION FAILURE %s:%d: [%s]\n",    \
+				__FILE__, __LINE__, #x);              \
+		exit(1);                                      \
+	}                                                 \
+} while(0)
+
+#else
+
+#define FAILIF(cond, msg...) do { \
+	if (unlikely(cond)) {         \
+		fprintf(stderr, ##msg);   \
+		exit(1);                  \
+	}                             \
+} while(0)
+
+/* No debug */
+#define ASSERT(x)   do { } while(0)
+
+#endif/* DEBUG */
+
+#define FAILIF_LIBELF(cond, function) \
+    FAILIF(cond, "%s(): %s\n", #function, elf_errmsg(elf_errno()));
+
+static inline void *MALLOC(unsigned int size) 
+{
+    void *m = malloc(size);
+    FAILIF(NULL == m, "malloc(%d) failed!\n", size);
+    return m;
+}
+
+static inline void *CALLOC(unsigned int num_entries, unsigned int entry_size) 
+{
+    void *m = calloc(num_entries, entry_size);
+    FAILIF(NULL == m, "calloc(%d, %d) failed!\n", num_entries, entry_size);
+    return m;
+}
+
+static inline void *REALLOC(void *ptr, unsigned int size) 
+{
+    void *m = realloc(ptr, size);
+    FAILIF(NULL == m, "realloc(%p, %d) failed!\n", ptr, size);
+    return m;
+}
+
+static inline void FREE(void *ptr)
+{
+    free(ptr);
+}
+
+static inline void FREEIF(void *ptr)
+{
+    if (ptr) FREE(ptr);
+}
+
+#define PRINT(x...)  do {                             \
+    extern int quiet_flag;                            \
+    if(likely(!quiet_flag))                           \
+        fprintf(stdout, ##x);                         \
+} while(0)
+
+#define ERROR(x...) fprintf(stderr, ##x)
+
+#define INFO(x...)  do {                              \
+    extern int verbose_flag;                          \
+    if(unlikely(verbose_flag))                        \
+        fprintf(stdout, ##x);                         \
+} while(0)
+
+/* Prints a hex and ASCII dump of the selected buffer to the selected stream. */
+int dump_hex_buffer(FILE *s, void *b, size_t l, size_t elsize);
+
+#endif/*DEBUG_H*/
diff --git a/tools/lsd/hash.c b/tools/lsd/hash.c
new file mode 100644
index 0000000..bbac675
--- /dev/null
+++ b/tools/lsd/hash.c
@@ -0,0 +1,29 @@
+#include <common.h>
+#include <debug.h>
+#include <libelf.h>
+#include <hash.h>
+#include <string.h>
+
+int hash_lookup(Elf *elf, 
+                Elf_Data *hash,
+                Elf_Data *symtab,
+                Elf_Data *symstr,
+                const char *symname)
+{
+    Elf32_Word *hash_data = (Elf32_Word *)hash->d_buf;
+    Elf32_Word index;
+    Elf32_Word nbuckets = *hash_data++;
+    Elf32_Word *buckets = ++hash_data;
+    Elf32_Word *chains  = hash_data + nbuckets;
+
+    index = buckets[elf_hash(symname) % nbuckets];
+    while(index != STN_UNDEF &&
+          strcmp((char *)symstr->d_buf + 
+                 ((Elf32_Sym *)symtab->d_buf)[index].st_name,
+                 symname))
+    {
+        index = chains[index];
+    }
+
+    return index;
+}
diff --git a/tools/lsd/hash.h b/tools/lsd/hash.h
new file mode 100644
index 0000000..af29b9e
--- /dev/null
+++ b/tools/lsd/hash.h
@@ -0,0 +1,14 @@
+#ifndef HASH_H
+#define HASH_H
+
+#include <common.h>
+#include <libelf.h>
+#include <gelf.h>
+
+int hash_lookup(Elf *elf, 
+                Elf_Data *hash,
+                Elf_Data *symtab,
+                Elf_Data *symstr,
+                const char *symname);
+
+#endif/*HASH_H*/
diff --git a/tools/lsd/lsd.c b/tools/lsd/lsd.c
new file mode 100644
index 0000000..03c235b
--- /dev/null
+++ b/tools/lsd/lsd.c
@@ -0,0 +1,777 @@
+#include <stdio.h>
+#include <common.h>
+#include <debug.h>
+#include <libelf.h>
+#include <libebl.h>
+#include <elf.h>
+#include <gelf.h>
+#include <string.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <hash.h>
+#include <lsd.h>
+
+extern int verbose_flag;
+
+typedef struct source_t source_t;
+
+typedef struct {
+    Elf_Scn *scn;
+    GElf_Shdr shdr;
+    Elf_Data *data;
+} section_info_t;
+
+typedef struct next_export_t { 
+    source_t *source;
+    int next_idx;
+} next_export_t;
+
+struct source_t {
+    source_t *next;
+    int visited;
+
+    char *name;  /* full path name of this executable file */
+    /* ELF-related information: */
+    Elf *elf;
+    int elf_fd;
+    GElf_Ehdr elf_hdr;
+    size_t shstrndx;
+    int shnum; /* number of sections */
+
+    section_info_t symtab;
+    section_info_t strtab;
+    section_info_t dynamic;
+    section_info_t hash;
+
+    section_info_t *relocations;
+    int num_relocations; /* number of relocs (<= relocations_size) */
+    int relocations_size; /* sice of array -- NOT number of relocs! */
+
+	/* satisfied_execs: array containing pointers to the libraries or 
+	   executables that this executable satisfies symbol references for. */
+	source_t **satisfied_execs;
+    int num_satisfied_execs;
+    int satisfied_execs_size;
+
+    /* satisfied: array is parallel to symbol table; for each undefined symbol 
+       in that array, we maintain a flag stating whether that symbol has been 
+       satisfied, and if so, by which library.  This applies both to executable
+       files and libraries.
+    */
+    source_t **satisfied;
+
+    /* exports: array is parallel to symbol table; for each global symbol 
+       in that array, we maintain a flag stating whether that symbol satisfies 
+       a dependency in some other file.  num_syms is the length of the exports
+       array, as well as the satisfied array. This applied to libraries only.
+
+       next_exports:  this is a bit tricky.  We use this field to maintain a 
+       linked list of source_t for each global symbol of a shared library. 
+       For a shared library's global symbol at index N has the property that
+       exports[N] is the head of a linked list (threaded through next_export)
+       of all source_t that this symbol resolves a reference to.  For example, 
+       if symbol printf has index 1000 in libc.so, and an executable A and 
+       library L use printf, then the source_t entry corresponding to libc.so
+       will have exports[1000] be a linked list that contains the nodes for 
+       application A and library L.
+    */
+
+    next_export_t *exports;
+    /* num_exported is the number of symbols in this file actually used by
+       somebody else;  it's not the size of the exports array. */
+    int num_exported;
+    next_export_t *next_export;
+    int num_next_export;
+    int next_export_size;
+
+    int num_syms; /* number of symbols in symbol table.  This is the length of
+                     both exports[] and satisfied[] arrays. */
+
+    /* This is an array that contains one element for each library dependency
+       listed in the executable or shared library. */
+    source_t **lib_deps; /* list of library dependencies */
+    int num_lib_deps; /* actual number of library dependencies */
+    int lib_deps_size; /* size of lib_deps array--NOT actual number of deps! */
+
+};
+
+static source_t *sources = NULL;
+
+static char * find_file(const char *libname, 
+                        char **lib_lookup_dirs, 
+                        int num_lib_lookup_dirs);
+
+static inline source_t* find_source(const char *name,
+                                    char **lib_lookup_dirs, 
+                                    int num_lib_lookup_dirs) {
+    source_t *trav = sources;
+	char *full = find_file(name, lib_lookup_dirs, num_lib_lookup_dirs);
+    FAILIF(full == NULL, "Cannot construct full path for file [%s]!\n", name);
+    while (trav) {
+        if (!strcmp(trav->name, full))
+            break;
+        trav = trav->next;
+    }
+	free(full);
+    return trav;
+}
+
+static inline void add_to_sources(source_t *src) {
+    src->next = sources;
+    sources = src;
+}
+
+static source_t* init_source(char *full_path) {
+    source_t *source = (source_t *)CALLOC(1, sizeof(source_t));
+
+    ASSERT(full_path);
+    source->name = full_path;
+    source->elf_fd = -1;
+
+    INFO("Opening %s...\n", full_path);
+    source->elf_fd = open(full_path, O_RDONLY);
+    FAILIF(source->elf_fd < 0, "open(%s): %s (%d)\n", 
+           full_path, 
+           strerror(errno), 
+           errno);
+    INFO("Calling elf_begin(%s)...\n", full_path);
+    source->elf = elf_begin(source->elf_fd, ELF_C_READ, NULL);
+    FAILIF_LIBELF(source->elf == NULL, elf_begin);
+
+    /* libelf can recognize COFF and A.OUT formats, but we handle only ELF. */
+    if (elf_kind(source->elf) != ELF_K_ELF) {
+        ERROR("Input file %s is not in ELF format!\n", full_path);
+        return NULL;
+    }
+
+    /* Make sure this is a shared library or an executable. */
+    {
+        INFO("Making sure %s is a shared library or an executable...\n", 
+             full_path);
+        FAILIF_LIBELF(0 == gelf_getehdr(source->elf, &source->elf_hdr), gelf_getehdr);
+        FAILIF(source->elf_hdr.e_type != ET_DYN && 
+               source->elf_hdr.e_type != ET_EXEC,
+               "%s must be a shared library (elf type is %d, expecting %d).\n", 
+               full_path,
+               source->elf_hdr.e_type, 
+               ET_DYN);
+    }
+
+    /* Get the index of the section-header-strings-table section. */
+    FAILIF_LIBELF(elf_getshstrndx (source->elf, &source->shstrndx) < 0, 
+                  elf_getshstrndx);
+
+    FAILIF_LIBELF(elf_getshnum (source->elf, &source->shnum) < 0, elf_getshnum);
+
+    /* Find various sections. */
+    size_t scnidx;
+    Elf_Scn *scn;
+    GElf_Shdr *shdr, shdr_mem;
+    INFO("Locating %d sections in %s...\n", source->shnum, full_path);
+    for (scnidx = 1; scnidx < source->shnum; scnidx++) {
+        scn = elf_getscn(source->elf, scnidx);
+        FAILIF_LIBELF(NULL == scn, elf_getscn);
+        shdr = gelf_getshdr(scn, &shdr_mem);
+        FAILIF_LIBELF(NULL == shdr, gelf_getshdr);
+        INFO("\tfound section [%s]...\n", elf_strptr(source->elf, source->shstrndx, shdr->sh_name));
+        if (shdr->sh_type == SHT_DYNSYM) {
+            source->symtab.scn = scn;
+            source->symtab.data = elf_getdata(scn, NULL);
+            FAILIF_LIBELF(NULL == source->symtab.data, elf_getdata);
+            memcpy(&source->symtab.shdr, shdr, sizeof(GElf_Shdr));
+
+            /* The sh_link field of the section header of the symbol table
+               contains the index of the associated strings table. */
+            source->strtab.scn = elf_getscn(source->elf, 
+                                            source->symtab.shdr.sh_link);
+            FAILIF_LIBELF(NULL == source->strtab.scn, elf_getscn);
+            FAILIF_LIBELF(NULL == gelf_getshdr(scn, &source->strtab.shdr),
+                          gelf_getshdr);
+            source->strtab.data = elf_getdata(source->strtab.scn, NULL);
+            FAILIF_LIBELF(NULL == source->strtab.data, elf_getdata);
+        }
+        else if (shdr->sh_type == SHT_DYNAMIC) {
+            source->dynamic.scn = scn;
+            source->dynamic.data = elf_getdata(scn, NULL);
+            FAILIF_LIBELF(NULL == source->symtab.data, elf_getdata);
+            memcpy(&source->dynamic.shdr, shdr, sizeof(GElf_Shdr));
+        }
+        else if (shdr->sh_type == SHT_HASH) {
+            source->hash.scn = scn;
+            source->hash.data = elf_getdata(scn, NULL);
+            FAILIF_LIBELF(NULL == source->hash.data, elf_getdata);
+            memcpy(&source->hash.shdr, shdr, sizeof(GElf_Shdr));
+        }
+        else if (shdr->sh_type == SHT_REL || shdr->sh_type == SHT_RELA) {
+            if (source->num_relocations == source->relocations_size) {
+                source->relocations_size += 5;
+                source->relocations = 
+                    (section_info_t *)REALLOC(source->relocations,
+                                              source->relocations_size *
+                                              sizeof(section_info_t));
+            }
+            section_info_t *reloc = 
+                source->relocations + source->num_relocations;
+            reloc->scn = scn;
+            reloc->data = elf_getdata(scn, NULL);
+            FAILIF_LIBELF(NULL == reloc->data, elf_getdata);
+            memcpy(&reloc->shdr, shdr, sizeof(GElf_Shdr));
+            source->num_relocations++;
+        }
+    }
+
+    if (source->dynamic.scn == NULL) {
+        INFO("File [%s] does not have a dynamic section!\n", full_path);
+        return 0;
+    }
+
+    FAILIF(source->symtab.scn == NULL, 
+           "File [%s] does not have a dynamic symbol table!\n",
+           full_path);
+
+    FAILIF(source->hash.scn == NULL, 
+           "File [%s] does not have a hash table!\n",
+           full_path);
+    FAILIF(source->hash.shdr.sh_link != elf_ndxscn(source->symtab.scn),
+           "Hash points to section %d, not to %d as expected!\n",
+           source->hash.shdr.sh_link,
+           elf_ndxscn(scn));
+
+    /* Now, find out how many symbols we have and allocate the array of 
+       satisfied symbols.
+
+       NOTE: We don't count the number of undefined symbols here; we will 
+       iterate over the symbol table later, and count them then, when it is 
+       more convenient. 
+    */
+    size_t symsize = gelf_fsize (source->elf, 
+                                 ELF_T_SYM, 
+                                 1, source->elf_hdr.e_version);
+    ASSERT(symsize);
+
+    source->num_syms = source->symtab.data->d_size / symsize;
+    source->satisfied = (source_t **)CALLOC(source->num_syms, 
+                                            sizeof(source_t *));
+    source->exports = (source_t **)CALLOC(source->num_syms, 
+                                          sizeof(next_export_t));
+
+    source->num_exported = 0;
+    source->satisfied_execs = NULL;
+    source->num_satisfied_execs = 0;
+    source->satisfied_execs_size = 0;
+
+    add_to_sources(source);
+    return source;
+}
+
+static void destroy_source(source_t *source) {
+    FREE(source->satisfied_execs);
+    FREE(source->satisfied);
+    FREE(source->exports);
+    FREE(source->next_export);    
+    FREE(source->lib_deps); /* list of library dependencies */
+    FAILIF_LIBELF(elf_end(source->elf), elf_end);
+    FAILIF(close(source->elf_fd) < 0, "Could not close file %s: %s (%d)!\n", 
+           source->name, strerror(errno), errno);
+    FREE(source->name);
+    FREE(source);
+}
+
+static void print_needed_libs(source_t *source)
+{
+	size_t idx;
+	for (idx = 0; idx < source->num_lib_deps; idx++) {
+		PRINT("%s:%s\n", 
+			  source->name, 
+			  source->lib_deps[idx]->name);
+	}
+}
+
+static int is_symbol_imported(source_t *source,
+                              GElf_Sym *sym, 
+                              size_t symidx)
+{
+    const char *symname = elf_strptr(source->elf,
+                                     elf_ndxscn(source->strtab.scn),
+                                     sym->st_name);
+
+    /* A symbol is imported by an executable or a library if it is undefined
+       and is either global or weak. There is an additional case for 
+       executables that we will check below. */
+    if (sym->st_shndx == SHN_UNDEF &&
+        (GELF_ST_BIND(sym->st_info) == STB_GLOBAL ||
+         GELF_ST_BIND(sym->st_info) == STB_WEAK)) {
+        INFO("*** symbol [%s:%s] is imported (UNDEFIEND).\n",
+             source->name,
+             symname);
+        return 1;
+    }
+
+#ifdef ARM_SPECIFIC_HACKS
+    /* A symbol is imported by an executable if is marked as an undefined 
+       symbol--this is standard to all ELF formats.  Alternatively, according 
+       to the ARM specifications, a symbol in a BSS section that is also marked
+       by an R_ARM_COPY relocation is also imported. */
+
+    if (source->elf_hdr.e_type != ET_EXEC) {
+        INFO("is_symbol_imported(): [%s] is a library, "
+             "no further checks.\n", source->name);
+        return 0;
+    }
+
+    /* Is the symbol in the BSS section, and is there a COPY relocation on 
+       that symbol? */
+    INFO("*** [%s:%s] checking further to see if symbol is imported.\n",
+         source->name, symname);
+    if (sym->st_shndx < source->shnum) {
+        /* Is it the .bss section? */
+        Elf_Scn *scn = elf_getscn(source->elf, sym->st_shndx);
+        FAILIF_LIBELF(NULL == scn, elf_getscn);
+        GElf_Shdr *shdr, shdr_mem;
+        shdr = gelf_getshdr(scn, &shdr_mem);
+        FAILIF_LIBELF(NULL == shdr, gelf_getshdr);
+        if (!strcmp(".bss", elf_strptr(source->elf,
+                                       source->shstrndx,
+                                       shdr->sh_name)))
+        {
+            /* Is there an R_ARM_COPY relocation on this symbol?  Iterate 
+               over the list of relocation sections and scan each section for
+               an entry that matches the symbol. */
+            size_t idx;
+            for (idx = 0; idx < source->num_relocations; idx++) {
+                section_info_t *reloc = source->relocations + idx;
+                /* Does the relocation section refer to the symbol table in
+                   which this symbol resides, and does it relocate the .bss
+                   section? */
+                if (reloc->shdr.sh_link == elf_ndxscn(source->symtab.scn) &&
+                    reloc->shdr.sh_info == sym->st_shndx)
+                {
+                    /* Go over the relocations and see if any of them matches
+                       our symbol. */
+                    size_t nrels = reloc->shdr.sh_size / reloc->shdr.sh_entsize;
+                    size_t relidx, newidx;
+                    if (reloc->shdr.sh_type == SHT_REL) {
+                        for (newidx = relidx = 0; relidx < nrels; ++relidx) {
+                            GElf_Rel rel_mem;
+                            FAILIF_LIBELF(gelf_getrel (reloc->data, 
+                                                       relidx, 
+                                                       &rel_mem) == NULL,
+                                          gelf_getrel);
+                            if (GELF_R_TYPE(rel_mem.r_info) == R_ARM_COPY &&
+                                GELF_R_SYM (rel_mem.r_info) == symidx)
+                            {
+                                INFO("*** symbol [%s:%s] is imported "
+                                     "(DEFINED, REL-COPY-RELOCATED).\n",
+                                     source->name,
+                                     symname);
+                                return 1;
+                            }
+                        } /* for each rel entry... */
+                    } else {
+                        for (newidx = relidx = 0; relidx < nrels; ++relidx) {
+                            GElf_Rela rel_mem;
+                            FAILIF_LIBELF(gelf_getrela (reloc->data, 
+                                                        relidx, 
+                                                        &rel_mem) == NULL,
+                                          gelf_getrela);
+                            if (GELF_R_TYPE(rel_mem.r_info) == R_ARM_COPY &&
+                                GELF_R_SYM (rel_mem.r_info) == symidx)
+                            {
+                                INFO("*** symbol [%s:%s] is imported "
+                                     "(DEFINED, RELA-COPY-RELOCATED).\n",
+                                     source->name,
+                                     symname);
+                                return 1;
+                            }
+                        } /* for each rela entry... */
+                    } /* if rel else rela */
+                }
+            }
+        }
+    }
+#endif/*ARM_SPECIFIC_HACKS*/
+
+    return 0;
+}
+
+static void resolve(source_t *source) {
+    /* Iterate the symbol table.  For each undefined symbol, scan the 
+       list of dependencies till we find a global symbol in one of them that 
+       satisfies the undefined reference.  At this point, we update both the 
+       satisfied[] array of the sources entry, as well as the exports array of 
+       the dependency where we found the match.
+    */
+
+    GElf_Sym *sym, sym_mem;
+    size_t symidx;
+    for (symidx = 0; symidx < source->num_syms; symidx++) {
+        sym = gelf_getsymshndx(source->symtab.data, 
+                               NULL,
+                               symidx,
+                               &sym_mem,
+                               NULL);
+        FAILIF_LIBELF(NULL == sym, gelf_getsymshndx);
+        if (is_symbol_imported(source, sym, symidx)) 
+		{
+            /* This is an undefined symbol.  Go over the list of libraries 
+               and look it up. */
+            size_t libidx;
+			int found = 0;
+			source_t *last_found = NULL;
+			const char *symname = elf_strptr(source->elf,
+											 elf_ndxscn(source->strtab.scn),
+											 sym->st_name);
+            for (libidx = 0; libidx < source->num_lib_deps; libidx++) {
+                source_t *lib = source->lib_deps[libidx];
+                int lib_symidx = hash_lookup(lib->elf,
+                                             lib->hash.data,
+                                             lib->symtab.data,
+                                             lib->strtab.data,
+                                             symname);
+                if (STN_UNDEF != lib_symidx)
+                {
+					/* We found the symbol--now check to see if it is global 
+					   or weak.  If this is the case, then the symbol satisfies
+					   the dependency. */
+					GElf_Sym *lib_sym, lib_sym_mem;
+					lib_sym = gelf_getsymshndx(lib->symtab.data, 
+											   NULL,
+											   lib_symidx,
+											   &lib_sym_mem,
+											   NULL);
+					FAILIF_LIBELF(NULL == lib_sym, gelf_getsymshndx);
+
+					if(lib_sym->st_shndx != STN_UNDEF &&
+					   (GELF_ST_BIND(lib_sym->st_info) == STB_GLOBAL ||
+						GELF_ST_BIND(lib_sym->st_info) == STB_WEAK))
+					{
+						/* We found the symbol! Update the satisfied array at this
+						   index location. */
+						source->satisfied[symidx] = lib;
+						/* Now, link this structure into the linked list 
+						   corresponding to the found symbol in the library's 
+						   global array. */
+                        if (source->num_next_export == source->next_export_size) {
+                            source->next_export_size += 30;
+                            source->next_export = 
+                                (source_t **)REALLOC(source->next_export,
+                                                     source->next_export_size *
+                                                     sizeof(struct next_export_t));
+                        }
+                        source->next_export[source->num_next_export] = lib->exports[lib_symidx];
+                        lib->exports[lib_symidx].source = source;
+                        lib->exports[lib_symidx].next_idx = source->num_next_export;
+
+                        source->num_next_export++;
+                        lib->num_exported++;
+
+                        INFO("[%s:%s (index %d)] satisfied by [%s] (index %d)\n",
+							 source->name,
+							 symname,
+							 symidx,
+							 lib->name,
+							 lib_symidx);
+						if (found) {
+							if (found == 1) {
+								found++;
+								ERROR("ERROR: multiple definitions found for [%s:%s]!\n",
+									  source->name, symname);
+								ERROR("\tthis definition     [%s]\n", lib->name);
+							}
+							ERROR("\tprevious definition [%s]\n", last_found->name);
+						}
+
+						last_found = lib;
+						if (!found) found = 1;
+					}
+                }
+            }
+			if(found == 0) {
+				ERROR("ERROR: could not find match for %s:%s.\n", 
+					  source->name, 
+					  symname);
+			}
+        } /* if we found the symbol... */
+    } /* for each symbol... */
+} /* resolve() */
+
+static void print_used_symbols(source_t *source) {
+
+    int name_len = strlen(source->name);
+    static const char ext[] = ".syms";
+    char *filter = (char *)MALLOC(name_len + sizeof(ext));
+    strcpy(filter, source->name);
+    strcpy(filter + name_len, ext);
+
+    FILE *fp = fopen(filter, "w+");
+    FAILIF(NULL == fp, 
+           "Can't open %s: %s (%d)\n", 
+           filter, 
+           strerror(errno), errno);
+    
+    /* Is anybody using the symbols defined in source? */
+
+    if (source->num_exported > 0) {
+        INFO("[%s] exports %d symbols to %d libraries and executables.\n",
+             source->name,
+             source->num_exported,
+             source->num_satisfied_execs);
+        size_t symidx;
+        for (symidx = 0; symidx < source->num_syms; symidx++) {
+            if (source->exports[symidx].source != NULL) {
+                GElf_Sym *sym, sym_mem;
+                sym = gelf_getsymshndx(source->symtab.data, 
+                                       NULL,
+                                       symidx,
+                                       &sym_mem,
+                                       NULL);
+                FAILIF_LIBELF(NULL == sym, gelf_getsymshndx);
+                fprintf(fp, "%s\n", elf_strptr(source->elf,
+                                               elf_ndxscn(source->strtab.scn),
+                                               sym->st_name));
+            }
+        }
+    }
+    else if (source->num_satisfied_execs > 0) {
+
+        /*  Is the source listed as a depenency on anyone?  If so, then the source exports no symbols
+            to anyone, but someone lists it as a dependency, which is unnecessary, so we print a warning.
+         */
+
+        ERROR("WARNING: [%s] is listed as a dependency in: ", source->name);
+        int i;
+        for (i = 0; i < source->num_satisfied_execs; i++) {
+            ERROR(" [%s],", source->satisfied_execs[i]->name);
+        }
+        ERROR(" but none of its symbols are used!.\n");
+    }
+#if 0 /* This is not really an error--a library's symbols may not be used anyone as specified in the ELF file,
+         but someone may still open a library via dlopen(). 
+      */
+    else {
+        ERROR("WARNING: None of [%s]'s symbols are used by any library or executable!\n", source->name);
+    }
+#endif
+
+	fclose(fp);
+    FREE(filter);
+}
+
+static void print_symbol_references(source_t *source) {
+
+    int name_len = strlen(source->name);
+    static const char ext[] = ".info";
+    char *filter = (char *)MALLOC(name_len + sizeof(ext));
+    strcpy(filter, source->name);
+    strcpy(filter + name_len, ext);
+
+    FILE *fp = fopen(filter, "w+");
+    FAILIF(NULL == fp, 
+           "Can't open %s: %s (%d)\n", 
+           filter, 
+           strerror(errno), errno);
+
+    if (source->num_exported > 0) {
+        size_t symidx;
+        for (symidx = 0; symidx < source->num_syms; symidx++) {
+            if (source->exports[symidx].source != NULL) {
+                const char *symname;
+                GElf_Sym *sym, sym_mem;
+                sym = gelf_getsymshndx(source->symtab.data, 
+                                       NULL,
+                                       symidx,
+                                       &sym_mem,
+                                       NULL);
+                FAILIF_LIBELF(NULL == sym, gelf_getsymshndx);
+                symname = elf_strptr(source->elf, 
+                                     elf_ndxscn(source->strtab.scn),
+                                     sym->st_name);
+                fprintf(fp, "%s\n", symname);
+                next_export_t *export = &source->exports[symidx];
+                while (export->source != NULL) {
+                    //fprintf(stderr, "%s:%s\n", symname, export->source->name);
+                    fprintf(fp, "\t%s\n", export->source->name);
+                    export = &export->source->next_export[export->next_idx];
+                }
+            }
+        }
+    }
+
+	fclose(fp);
+    FREE(filter);
+}
+
+static char * find_file(const char *libname, 
+                        char **lib_lookup_dirs, 
+                        int num_lib_lookup_dirs) {
+    if (libname[0] == '/') {
+        /* This is an absolute path name--just return it. */
+        INFO("ABSOLUTE PATH: [%s].\n", libname);
+        return strdup(libname);
+    } else {
+        /* First try the working directory. */
+        int fd;
+        if ((fd = open(libname, O_RDONLY)) > 0) {
+            close(fd);
+            INFO("FOUND IN CURRENT DIR: [%s].\n", libname);
+            return strdup(libname);
+        } else {
+            /* Iterate over all library paths.  For each path, append the file
+               name and see if there is a file at that place. If that fails, 
+               bail out. */
+
+            char *name;
+            while (num_lib_lookup_dirs--) {
+                size_t lib_len = strlen(*lib_lookup_dirs);
+                /* one extra character for the slash, and another for the 
+                   terminating NULL. */
+                name = (char *)MALLOC(lib_len + strlen(libname) + 2);
+                strcpy(name, *lib_lookup_dirs);
+                name[lib_len] = '/';
+                strcpy(name + lib_len + 1, libname);
+                if ((fd = open(name, O_RDONLY)) > 0) {
+                    close(fd);
+                    INFO("FOUND: [%s] in [%s].\n", libname, name);
+                    return name;
+                }
+                INFO("NOT FOUND: [%s] in [%s].\n", libname, name);
+                free(name);
+            }
+        }
+    }
+    return NULL;
+}
+
+static source_t* process_library(const char *libname,
+                                 char **lib_lookup_dirs, 
+                                 int num_lib_lookup_dirs) {
+    source_t *source = find_source(libname, lib_lookup_dirs, num_lib_lookup_dirs);
+    if (NULL == source) {
+        INFO("Processing [%s].\n", libname);
+        char *full = find_file(libname, lib_lookup_dirs, num_lib_lookup_dirs);
+        FAILIF(NULL == full, 
+               "Could not find [%s] in the current directory or in any of "
+               "the search paths!\n", libname);
+        source = init_source(full);
+        if (source) {
+            GElf_Dyn *dyn, dyn_mem;
+            size_t dynidx;
+            size_t numdyn =
+            source->dynamic.shdr.sh_size / 
+            source->dynamic.shdr.sh_entsize;
+
+            for (dynidx = 0; dynidx < numdyn; dynidx++) {
+                dyn = gelf_getdyn (source->dynamic.data, 
+                                   dynidx, 
+                                   &dyn_mem);
+                FAILIF_LIBELF(NULL == dyn, gelf_getdyn);
+                if (dyn->d_tag == DT_NEEDED) {
+                    /* Process the needed library recursively. */
+                    const char *dep_lib =
+                    elf_strptr (source->elf, 
+                                source->dynamic.shdr.sh_link, 
+                                dyn->d_un.d_val);
+                    INFO("[%s] depends on [%s].\n", libname, dep_lib);
+                    source_t *dep = process_library(dep_lib, 
+                                                    lib_lookup_dirs,
+                                                    num_lib_lookup_dirs);
+
+                    /* Tell dep that source depends on it. */
+                    if (dep->num_satisfied_execs == dep->satisfied_execs_size) {
+                        dep->satisfied_execs_size += 10;
+                        dep->satisfied_execs = 
+                            REALLOC(dep->satisfied_execs,
+                                    dep->satisfied_execs_size *
+                                    sizeof(source_t *));
+                    }
+                    dep->satisfied_execs[dep->num_satisfied_execs++] = source;
+
+                    /* Add the library to the dependency list. */
+                    if (source->num_lib_deps == source->lib_deps_size) {
+                        source->lib_deps_size += 10;
+                        source->lib_deps = REALLOC(source->lib_deps, 
+                                                   source->lib_deps_size *
+                                                   sizeof(source_t *));
+                    }
+                    source->lib_deps[source->num_lib_deps++] = dep;
+                }
+            } /* for each dynamic entry... */
+        }
+    } else INFO("[%s] has been processed already.\n", libname);
+
+    return source;
+}
+
+void lsd(char **execs, int num_execs,
+		 int list_needed_libs,
+		 int print_info,
+         char **lib_lookup_dirs, int num_lib_lookup_dirs) {
+
+    source_t *source; /* for general usage */
+    int input_idx;
+
+    for (input_idx = 0; input_idx < num_execs; input_idx++) {
+        INFO("executable: [%s]\n", execs[input_idx]);
+        /* Here process library is actually processing the top-level executable
+           files. */
+        process_library(execs[input_idx], lib_lookup_dirs, num_lib_lookup_dirs);
+        /* if source is NULL, then the respective executable is static */
+        /* Mark the source as an executable */
+    } /* for each input executable... */
+
+	if (list_needed_libs) {
+		source = sources;
+		while (source) {
+			print_needed_libs(source);
+			source = source->next;
+		}
+	}
+
+    /* Now, for each entry in the sources array, iterate its symbol table.  For
+       each undefined symbol, scan the list of dependencies till we find a 
+       global symbol in one of them that satisfies the undefined reference.  
+       At this point, we update both the satisfied[] array of the sources entry, 
+       as well as the exports array of the dependency where we found the match.
+    */
+
+    source = sources;
+    while (source) {
+        resolve(source);
+        source = source->next;
+    }
+
+    /* We are done!  Since the end result of our calculations is a set of 
+       symbols for each library that other libraries or executables link 
+       against, we iterate over the set of libraries one last time, and for
+       each symbol that is marked as satisfying some dependence, we emit 
+       a line with the symbol's name to a text file derived from the library's
+       name by appending the suffix .syms to it. */
+
+    source = sources;
+    while (source) {
+        /* If it's a library, print the results. */
+        if (source->elf_hdr.e_type == ET_DYN) {
+			print_used_symbols(source);
+			if (print_info) 
+				print_symbol_references(source);
+		}
+        source = source->next;
+    }
+
+	/* Free the resources--you can't do it in the loop above because function 
+	   print_symbol_references() accesses nodes other than the one being 
+	   iterated over.
+	 */
+	source = sources;
+	while (source) {
+		source_t *old = source;
+		source = source->next;
+		/* Destroy the evidence. */
+		destroy_source(old);
+	}
+}
+
diff --git a/tools/lsd/lsd.h b/tools/lsd/lsd.h
new file mode 100644
index 0000000..883c423
--- /dev/null
+++ b/tools/lsd/lsd.h
@@ -0,0 +1,10 @@
+#ifndef LSD_H
+#define LSD_H
+
+void lsd(char **execs, int num_execs,
+		 int list_needed_libs,
+		 int print_info,
+         char **lib_lookup_dirs, 
+         int num_lib_lookup_dirs);
+
+#endif
diff --git a/tools/lsd/main.c b/tools/lsd/main.c
new file mode 100644
index 0000000..f29157a
--- /dev/null
+++ b/tools/lsd/main.c
@@ -0,0 +1,67 @@
+/* TODO:
+   1. check the ARM EABI version--this works for versions 1 and 2.
+   2. use a more-intelligent approach to finding the symbol table, symbol-string
+      table, and the .dynamic section.
+   3. fix the determination of the host and ELF-file endianness
+   4. write the help screen
+*/
+
+#include <stdio.h>
+#include <common.h>
+#include <debug.h>
+#include <libelf.h>
+#include <elf.h>
+#include <gelf.h>
+#include <cmdline.h>
+#include <string.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <lsd.h>
+
+/* Flag set by --verbose.  This variable is global as it is accessed by the
+   macro INFO() in multiple compilation unites. */
+int verbose_flag = 0;
+/* Flag set by --quiet.  This variable is global as it is accessed by the
+   macro PRINT() in multiple compilation unites. */
+int quiet_flag = 0;
+
+int main(int argc, char **argv)
+{
+    char **lookup_dirs = NULL;
+    int num_lookup_dirs;
+	int print_info;
+	int list_needed_libs;
+
+    /* Do not issue INFO() statements before you call get_options() to set 
+       the verbose flag as necessary.
+    */
+
+    int first = get_options(argc, argv,
+							&list_needed_libs,
+							&print_info,
+                            &lookup_dirs,
+                            &num_lookup_dirs,
+                            &verbose_flag);
+
+    if (first == argc) {
+        print_help();
+        FAILIF(1,  "You must specify at least one input ELF file!\n");
+    }
+
+    /* Check to see whether the ELF library is current. */
+    FAILIF (elf_version(EV_CURRENT) == EV_NONE, "libelf is out of date!\n");
+
+    /* List symbol dependencies... */
+    lsd(&argv[first], argc - first, 
+		list_needed_libs, print_info, 
+		lookup_dirs, num_lookup_dirs);
+
+    FREE(lookup_dirs);
+
+    return 0;
+} 
+