Further hacks to use an add-on Bionic linker copy, unfinished private/tml/android-use-bionic-linker-copy

Change-Id: I7c7e06ad172fc95912958c1f46baa74071f5d613

6 files changed, 133 insertions, 57 deletions

diff --git a/android/Bootstrap/src/org/libreoffice/android/Bootstrap.java b/android/Bootstrap/src/org/libreoffice/android/Bootstrap.java
index b97adfb6261a..db8745b8863a 100644
--- a/android/Bootstrap/src/org/libreoffice/android/Bootstrap.java
+++ b/android/Bootstrap/src/org/libreoffice/android/Bootstrap.java
@@ -292,8 +292,6 @@ public class Bootstrap extends NativeActivity
     // time by the package manager.
     static {
         System.loadLibrary("lo-bootstrap");
-        System.loadLibrary("gnustl_shared");
-        System.loadLibrary("libotouchlo");
     }
 }
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sal/android/bionic/linker/dlfcn.c b/sal/android/bionic/linker/dlfcn.c
index a476092daec1..04eb8f7ffa3b 100644
--- a/sal/android/bionic/linker/dlfcn.c
+++ b/sal/android/bionic/linker/dlfcn.c
@@ -19,8 +19,6 @@
 #include "linker.h"
 #include "linker_format.h"
 
-/* This file hijacks the symbols stubbed out in libdl.so. */
-
 #define DL_SUCCESS                    0
 #define DL_ERR_CANNOT_LOAD_LIBRARY    1
 #define DL_ERR_INVALID_LIBRARY_HANDLE 2
@@ -169,24 +167,45 @@ int __lo_dlclose(void* handle) {
     return result;
 }
 
-/* Dummy replacement for the libdl_info in the real system dlfcn.c. */
+//                     0000000000 11111111112 222222222 3
+//                     0123456789 01234567890 123456789 0
+#define LO_LIBLO_BOOTSTRAP_STRTAB                                       \
+                      "lo_dlopen\0lo_dlclose\0lo_dlsym\0lo_dladdr\0"
 
 void __lo_dummy_foo(void)
 {
 }
 
-#define ANDROID_LIBDL_STRTAB \
-                      "__lo_dummy_foo\0"
+/* The wrappers in lo-bootstrap.c */
+extern void *lo_dlopen(const char *path, int flags);
+extern void *lo_dlsym(void *handle, const char *symbol);
+extern int lo_dlclose(void *handle);
+extern int lo_dladdr(void *addr, Dl_info *info);
 
-static Elf32_Sym libdl_symtab[] = {
-      // total length of libdl_info.strtab, including trailing 0
+static Elf32_Sym liblo_bootstrap_symtab[] = {
+      // total length of liblo_bootstrap_info.strtab, including trailing 0
       // This is actually the the STH_UNDEF entry. Technically, it's
       // supposed to have st_name == 0, but instead, it points to an index
       // in the strtab with a \0 to make iterating through the symtab easier.
-    { st_name: sizeof(ANDROID_LIBDL_STRTAB) - 1,
+    { st_name: sizeof(LO_LIBLO_BOOTSTRAP_STRTAB) - 1,
+    },
+    { st_name: 0,   // starting index of the name in liblo_bootstrap_info.strtab
+      st_value: (Elf32_Addr) &lo_dlopen,
+      st_info: STB_GLOBAL << 4,
+      st_shndx: 1,
     },
-    { st_name: 0,   // starting index of the name in libdl_info.strtab
-      st_value: (Elf32_Addr) &__lo_dummy_foo,
+    { st_name: 10,
+      st_value: (Elf32_Addr) &lo_dlclose,
+      st_info: STB_GLOBAL << 4,
+      st_shndx: 1,
+    },
+    { st_name: 21,
+      st_value: (Elf32_Addr) &lo_dlsym,
+      st_info: STB_GLOBAL << 4,
+      st_shndx: 1,
+    },
+    { st_name: 30,
+      st_value: (Elf32_Addr) &lo_dladdr,
       st_info: STB_GLOBAL << 4,
       st_shndx: 1,
     },
@@ -194,35 +213,32 @@ static Elf32_Sym libdl_symtab[] = {
 
 /* Fake out a hash table with a single bucket.
  * A search of the hash table will look through
- * libdl_symtab starting with index [1], then
- * use libdl_chains to find the next index to
- * look at.  libdl_chains should be set up to
- * walk through every element in libdl_symtab,
+ * liblo_bootstrap_symtab starting with index [1], then
+ * use liblo_bootstrap_chains to find the next index to
+ * look at.  liblo_bootstrap_chains should be set up to
+ * walk through every element in liblo_bootstrap_symtab,
  * and then end with 0 (sentinel value).
  *
- * I.e., libdl_chains should look like
+ * I.e., liblo_bootstrap_chains should look like
  * { 0, 2, 3, ... N, 0 } where N is the number
- * of actual symbols, or nelems(libdl_symtab)-1
- * (since the first element of libdl_symtab is not
+ * of actual symbols, or nelems(liblo_bootstrap_symtab)-1
+ * (since the first element of liblo_bootstrap_symtab is not
  * a real symbol).
  *
  * (see _elf_lookup())
- *
- * Note that adding any new symbols here requires
- * stubbing them out in libdl.
  */
-static unsigned libdl_buckets[1] = { 1 };
-static unsigned libdl_chains[3] = { 0, 2, 0 };
+static unsigned liblo_bootstrap_buckets[1] = { 1 };
+static unsigned liblo_bootstrap_chains[5] = { 0, 2, 3, 4, 0 };
 
-soinfo libdl_info = {
-    name: "lo-dummy-libdl.so",
+soinfo liblo_bootstrap_info = {
+    name: "liblo-bootstrap.so",
     flags: FLAG_LINKED,
 
-    strtab: ANDROID_LIBDL_STRTAB,
-    symtab: libdl_symtab,
+    strtab: LO_LIBLO_BOOTSTRAP_STRTAB,
+    symtab: liblo_bootstrap_symtab,
 
     nbucket: 1,
-    nchain: 3,
-    bucket: libdl_buckets,
-    chain: libdl_chains,
+    nchain: 5,
+    bucket: liblo_bootstrap_buckets,
+    chain: liblo_bootstrap_chains,
 };
diff --git a/sal/android/bionic/linker/linker.cxx b/sal/android/bionic/linker/linker.cxx
index d43eedbf9be7..edcbf5e70d21 100644
--- a/sal/android/bionic/linker/linker.cxx
+++ b/sal/android/bionic/linker/linker.cxx
@@ -79,10 +79,10 @@ static int soinfo_link_image(soinfo *si);
 static int socount = 0;
 static soinfo sopool[SO_MAX];
 static soinfo *freelist = NULL;
-static soinfo *solist = &libdl_info;
-static soinfo *sonext = &libdl_info;
+static soinfo *solist = &liblo_bootstrap_info;
+static soinfo *sonext = &liblo_bootstrap_info;
 #if ALLOW_SYMBOLS_FROM_MAIN
-static soinfo *somain; /* main process, always the one after libdl_info */
+static soinfo *somain; /* main process, always the one after liblo_bootstrap_info */
 #endif
 
 
@@ -90,7 +90,7 @@ static char ldpaths_buf[LDPATH_BUFSIZE];
 static const char *ldpaths[LDPATH_MAX + 1];
 
 #if LINKER_DEBUG
-int debug_verbosity;
+int debug_verbosity = 2;
 #endif
 
 static int pid;
@@ -300,7 +300,7 @@ static void soinfo_free(soinfo* si)
     }
 
     /* prev will never be NULL, because the first entry in solist is
-       always the static libdl_info.
+       always the static liblo_bootstrap_info.
     */
     prev->next = si->next;
     if (si == sonext) sonext = prev;
diff --git a/sal/android/bionic/linker/linker.h b/sal/android/bionic/linker/linker.h
index 59c9530d6429..f826746ea027 100644
--- a/sal/android/bionic/linker/linker.h
+++ b/sal/android/bionic/linker/linker.h
@@ -169,7 +169,7 @@ struct soinfo
 };
 
 
-extern soinfo libdl_info;
+extern soinfo liblo_bootstrap_info;
 
 
 #include <asm/elf.h>
diff --git a/sal/android/bionic/linker/linker_debug.h b/sal/android/bionic/linker/linker_debug.h
index 48a7abf0d2c1..49919931a37e 100644
--- a/sal/android/bionic/linker/linker_debug.h
+++ b/sal/android/bionic/linker/linker_debug.h
@@ -33,6 +33,9 @@
 
 #ifndef LINKER_DEBUG
 #error LINKER_DEBUG should be defined to either 1 or 0 in Android.mk
+#else
+#undef LINKER_DEBUG
+#define LINKER_DEBUG 1
 #endif
 
 /* set LINKER_DEBUG_TO_LOG to 1 to send the logs to logcat,
diff --git a/sal/android/lo-bootstrap.c b/sal/android/lo-bootstrap.c
index 4703b900a3f9..02229a153b66 100644
--- a/sal/android/lo-bootstrap.c
+++ b/sal/android/lo-bootstrap.c
@@ -69,6 +69,9 @@
 
 #define MAX(a,b) ((a) > (b) ? (a) : (b))
 
+/* The functions from our tweaked copy of the run-time linker, in
+ * sal/android/bionic/linker
+ */
 extern void *__lo_dlopen(const char *path, int flags);
 extern const char *__lo_dlerror(void);
 extern void *__lo_dlsym(void *handle, const char *symbol);
@@ -76,12 +79,6 @@ extern int __lo_dlclose(void *handle);
 extern int __lo_dladdr(void *addr, Dl_info *info);
 extern void __lo_linker_init(void);
 
-#define dlopen __lo_dlopen
-#define dlerror __lo_dlerror
-#define dlsym __lo_dlsym
-#define dlclose __lo_dlclose
-#define dladdr __lo_dladdr
-
 struct engine {
     int dummy;
 };
@@ -869,6 +866,13 @@ lo_dlopen(const char *library)
 
     struct timeval tv0, tv1, tvdiff;
 
+    FILE *maps;
+    char line[200];
+
+    /* libdl.so is special */
+    if (strcmp(library, "libdl.so") == 0)
+        return (void *) 42; /* ??? */
+
     rover = loaded_libraries;
     while (rover != NULL &&
            strcmp(rover->name, library) != 0)
@@ -923,16 +927,48 @@ lo_dlopen(const char *library)
     }
     free_ptrarray((void **) needed);
 
+    /* Find out if the real system run-time linker has loaded it */
+    maps = fopen("/proc/self/maps", "r");
+    if (maps == NULL) {
+        LOGE("lo_dladdr: Could not open /proc/self/maps: %s", strerror(errno));
+        return NULL;
+    }
+
+    found = 0;
+    while (fgets(line, sizeof(line), maps) != NULL &&
+           line[strlen(line)-1] == '\n') {
+        char file[sizeof(line)];
+        file[0] = '\0';
+        if (sscanf(line, "%*x-%*x %*s %*x %*x:%*x %*d %[^\n]", file) == 1) {
+            if (strcmp(file, full_name) == 0) {
+                found = 1;
+                break;
+            }
+        }
+    }
+    fclose(maps);
+
     gettimeofday(&tv0, NULL);
-    p = dlopen(full_name, RTLD_LOCAL);
+    if (found) {
+        /* It is already mapped, but it wasn't in our loaded_libraries list,
+         * presumably it's the system run-time linker that has loaded it.
+         */
+        LOGI("lo_dlopen: Using system dlopen()");
+        p = dlopen(full_name, RTLD_LOCAL);
+    } else {
+        /* Call our tweaked copy of the run-time linker to load it. */
+        LOGI("lo_dlopen: Using our tweaked__lo_dlopen()");
+        p = __lo_dlopen(full_name, RTLD_LOCAL);
+    }
     gettimeofday(&tv1, NULL);
     timersub(&tv1, &tv0, &tvdiff);
-    LOGI("dlopen(%s) = %p, %ld.%03lds",
+    LOGI("%s(%s) = %p, %ld.%03lds",
+         (found ? "dlopen" : "__lo_dlopen"),
          full_name, p,
          (long) tvdiff.tv_sec, (long) tvdiff.tv_usec / 1000);
     free(full_name);
     if (p == NULL)
-        LOGE("lo_dlopen: Error from dlopen(%s): %s", library, dlerror());
+        LOGE("lo_dlopen: Error from __lo_dlopen(%s): %s", library, (found ? dlerror() : __lo_dlerror()));
 
     new_loaded_lib = malloc(sizeof(*new_loaded_lib));
     new_loaded_lib->name = strdup(library);
@@ -949,10 +985,20 @@ void *
 lo_dlsym(void *handle,
          const char *symbol)
 {
-    void *p = dlsym(handle, symbol);
-    /* LOGI("dlsym(%p, %s) = %p", handle, symbol, p); */
+    int used_system_dlsym = 0;
+    void *p;
+
+    p = __lo_dlsym(handle, symbol);
+    LOGI("__lo_dlsym(%p, %s) = %p", handle, symbol, p);
+
+    if (p == NULL) {
+        used_system_dlsym = 1;
+        p = dlsym(handle, symbol);
+        LOGI("dlsym(%p, %s) = %p", handle, symbol, p);
+    }
+
     if (p == NULL)
-        LOGE("lo_dlsym: %s", dlerror());
+        LOGE("lo_dlsym: %s", (used_system_dlsym ? dlerror() : __lo_dlerror()));
     return p;
 }
 
@@ -966,12 +1012,17 @@ lo_dladdr(void *addr,
     int result;
     int found;
 
-    result = dladdr(addr, info);
+    result = __lo_dladdr(addr, info);
+    LOGI("__lo_dladdr(%p) = 0", addr);
+
     if (result == 0) {
-        /* LOGI("dladdr(%p) = 0", addr); */
-        return 0;
+        result = dladdr(addr, info);
+        LOGI("dladdr(%p) = 0", addr);
     }
 
+    if (result == 0)
+        return 0;
+
     maps = fopen("/proc/self/maps", "r");
     if (maps == NULL) {
         LOGE("lo_dladdr: Could not open /proc/self/maps: %s", strerror(errno));
@@ -1368,13 +1419,21 @@ patch(const char *symbol,
      * containing lo_main() already, libgnustl_shared.so will have
      * been brought in, too.
      */
-    libgnustl_shared = dlopen("libgnustl_shared.so", RTLD_LOCAL);
+    libgnustl_shared = __lo_dlopen("libgnustl_shared.so", RTLD_LOCAL);
+
+    if (libgnustl_shared == NULL)
+        libgnustl_shared = dlopen("libgnustl_shared.so", RTLD_LOCAL);
+
     if (libgnustl_shared == NULL) {
         LOGF("android_main: libgnustl_shared.so not mapped??");
         exit(0);
     }
 
-    code = dlsym(libgnustl_shared, symbol);
+    code = __lo_dlsym(libgnustl_shared, symbol);
+
+    if (code == NULL)
+        code = dlsym(libgnustl_shared, symbol);
+
     if (code == NULL) {
         LOGF("android_main: %s not found!?", plaintext);
         exit(0);
@@ -1586,7 +1645,7 @@ Java_org_libreoffice_android_Bootstrap_initVCL(JNIEnv* env,
 
     /* This obviously should be called only after libvcllo.so has been loaded */
 
-    InitVCLWrapper = dlsym(RTLD_DEFAULT, "InitVCLWrapper");
+    InitVCLWrapper = __lo_dlsym(RTLD_DEFAULT, "InitVCLWrapper");
     if (InitVCLWrapper == NULL) {
         LOGE("InitVCL: InitVCLWrapper not found");
         return;
@@ -1626,7 +1685,7 @@ Java_org_libreoffice_android_Bootstrap_setCommandArgs(JNIEnv* env,
         c_argv[0] = new_argv0;
     }
 
-    osl_setCommandArgs = dlsym(RTLD_DEFAULT, "osl_setCommandArgs");
+    osl_setCommandArgs = __lo_dlsym(RTLD_DEFAULT, "osl_setCommandArgs");
     if (osl_setCommandArgs == NULL) {
         LOGE("setCommandArgs: osl_setCommandArgs not found");
         return;
@@ -1644,7 +1703,7 @@ Java_org_libreoffice_android_Bootstrap_createWindowFoo(JNIEnv* env,
     (void) clazz;
 
     lo_dlopen("libvcllo.so");
-    createWindowFoo = dlsym(RTLD_DEFAULT, "createWindowFoo");
+    createWindowFoo = __lo_dlsym(RTLD_DEFAULT, "createWindowFoo");
     if (createWindowFoo == NULL) {
         LOGE("createWindowFoo: createWindowFoo not found");
         return 0;