Changeset c4049e6 in mainline

Timestamp:

2018-07-05T21:41:20Z (7 years ago)

Author:

Dzejrou <dzejrou@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

9283830

Parents:

9396c52

git-author:

Dzejrou <dzejrou@…> (2018-03-15 10:40:53)

git-committer:

Dzejrou <dzejrou@…> (2018-07-05 21:41:20)

Message:

c+cpp: added support for global static constructors destructors

Files:

• abi/include/abi/elf.h (modified) (1 diff)
• uspace/lib/c/arch/amd64/_link.ld.in (modified) (1 diff)
• uspace/lib/c/generic/elf/elf_load.c (modified) (1 diff)
• uspace/lib/c/generic/elf/elf_mod.c (modified) (1 diff)
• uspace/lib/c/generic/libc.c (modified) (3 diffs)
• uspace/lib/c/include/loader/pcb.h (modified) (2 diffs)
• uspace/lib/cpp/include/internal/abi.hpp (modified) (1 diff)
• uspace/lib/cpp/src/internal/runtime.cpp (modified) (2 diffs)
• uspace/lib/cpp/src/internal/unwind.cpp (modified) (1 diff)

abi/include/abi/elf.h

@@ -110 +110 @@
  * ELF section types
  */
-#define SHT_NULL      0
-#define SHT_PROGBITS  1
-#define SHT_SYMTAB    2
-#define SHT_STRTAB    3
-#define SHT_RELA      4
-#define SHT_HASH      5
-#define SHT_DYNAMIC   6
-#define SHT_NOTE      7
-#define SHT_NOBITS    8
-#define SHT_REL       9
-#define SHT_SHLIB     10
-#define SHT_DYNSYM    11
+#define SHT_NULL       0
+#define SHT_PROGBITS   1
+#define SHT_SYMTAB     2
+#define SHT_STRTAB     3
+#define SHT_RELA       4
+#define SHT_HASH       5
+#define SHT_DYNAMIC    6
+#define SHT_NOTE       7
+#define SHT_NOBITS     8
+#define SHT_REL        9
+#define SHT_SHLIB      10
+#define SHT_DYNSYM     11
 #define SHT_LOOS      0x60000000
 #define SHT_HIOS      0x6fffffff

uspace/lib/c/arch/amd64/_link.ld.in

@@ -55 +55 @@
         } :data
 
+    __dso_handle = .;
+
+        .init_array : {
+                PROVIDE_HIDDEN (__init_array_start = .);
+                KEEP (*(SORT_BY_INIT_PRIORITY(.init_array.*) SORT_BY_INIT_PRIORITY(.ctors.*)))
+                KEEP (*(.init_array .ctors))
+                PROVIDE_HIDDEN (__init_array_end = .);
+        }
+
+        .fini_array : {
+                PROVIDE_HIDDEN (__fini_array_start = .);
+                KEEP (*(SORT_BY_INIT_PRIORITY(.fini_array.*) SORT_BY_INIT_PRIORITY(.dtors.*)))
+                KEEP (*(.fini_array .dtors))
+                PROVIDE_HIDDEN (__fini_array_end = .);
+        }
+
         _end = .;
 

uspace/lib/c/generic/elf/elf_load.c

@@ -112 +112 @@
         pcb->dynamic = info->finfo.dynamic;
         pcb->rtld_runtime = info->env;
+        pcb->cpp_data = info->finfo.cpp_data;
 }
 

uspace/lib/c/generic/elf/elf_mod.c

@@ -198 +198 @@
         size_t phdr_len = header->e_phnum * header->e_phentsize;
 
+        elf->info->interp = NULL;
+        elf->info->dynamic = NULL;
+        elf->info->cpp_data.ctors_count = 0;
+        elf->info->cpp_data.dtors_count = 0;
+
         if (phdr_len > sizeof(phdr)) {
                 DPRINTF("more than %d program headers\n", phdr_cap);

uspace/lib/c/generic/libc.c

@@ -61 +61 @@
 #endif
 
+static bool env_setup = false;
 
-static bool env_setup = false;
+/**
+ * Used for C++ constructors/destructors
+ * and the GCC constructor/destructor extension.
+ */
+typedef void (*init_array_entry_t)();
+extern init_array_entry_t __init_array_start[];
+extern init_array_entry_t __init_array_end[];
+typedef void (*fini_array_entry_t)();
+extern fini_array_entry_t __fini_array_start[];
+extern fini_array_entry_t __fini_array_end[];
 
 void __libc_main(void *pcb_ptr)
@@ -115 +125 @@
 
         /*
+         * C++ Static constructor calls.
+         */
+        ptrdiff_t init_array_entries = (__init_array_end - __init_array_start);
+
+        for (int i = init_array_entries - 1; i > 0; --i)
+                __init_array_start[i]();
+
+        /*
          * Run main() and set task return value
          * according the result
@@ -124 +142 @@
 void __libc_exit(int status)
 {
+        /*
+         * GCC extension __attribute__((destructor)),
+         * C++ destructors are added to __cxa_finalize call
+         * when the respective constructor is called.
+         */
+        ptrdiff_t fini_array_entries = (__fini_array_end - __fini_array_start);
+
+        for (int i = 0; i < fini_array_entries; ++i)
+                __fini_array_start[i]();
+
         if (env_setup) {
                 __stdio_done();

uspace/lib/c/include/loader/pcb.h

@@ -36 +36 @@
 #ifndef LIBC_PCB_H_
 #define LIBC_PCB_H_
-
 
 typedef void (*entry_point_t)(void);
@@ -76 +75 @@
         /** Pointer to dynamic linker state structure (rtld_t). */
         void *rtld_runtime;
+        /** C++ related data. */
+        cpp_data_t cpp_data;
 } pcb_t;
 

uspace/lib/cpp/include/internal/abi.hpp

@@ -32 +32 @@
 namespace __cxxabiv1
 {
+    /**
+     * Static constructor/destructor helpers.
+     */
+
+    extern "C" int __cxa_atexit(void (*)(void*), void*, void*);
+
+    extern "C" void __cxa_finalize(void*);
+
     /**
      * Itanium C++ ABI type infos.

uspace/lib/cpp/src/internal/runtime.cpp

@@ -27 +27 @@
  */
 
+#include <cstdlib>
+#include <cstdint>
 #include <internal/abi.hpp>
+#include <exception>
 
 namespace __cxxabiv1
 {
+    namespace aux
+    {
+        struct destructor_t
+        {
+            void (*func)(void*);
+            void* ptr;
+            void* dso;
+        };
+
+        destructor_t* destructors{nullptr};
+        std::size_t destructor_count{0};
+        std::size_t destructor_size{32};
+
+        /**
+         * C atexit does not pass any arguments,
+         * but __cxa_finalize requires one so we
+         * use a wrapper.
+         */
+        void atexit_destructors()
+        {
+            __cxa_finalize(nullptr);
+        }
+    }
 
     /**
@@ -36 +62 @@
      * call of a pure virtual function cannot be made.
      */
-    // TODO: terminate in this
     extern "C" void __cxa_pure_call()
-    { /* DUMMY BODY */ }
+    {
+        std::terminate();
+    }
+
+    extern "C" int __cxa_atexit(void (*f)(void*), void* p, void* d)
+    {
+        if (!aux::destructors)
+        {
+            aux::destructors = new aux::destructor_t[aux::destructor_size];
+            std::atexit(aux::atexit_destructors);
+        }
+        else if (aux::destructor_count >= aux::destructor_size)
+        {
+            auto tmp = std::realloc(aux::destructors, aux::destructor_size * 2);
+
+            if (!tmp)
+                return -1;
+
+            aux::destructors = static_cast<aux::destructor_t*>(tmp);
+            aux::destructor_size *= 2;
+        }
+
+        auto& destr = aux::destructors[aux::destructor_count++];
+        destr.func = f;
+        destr.ptr = p;
+        destr.dso = d;
+
+        return 0;
+    }
+
+    extern "C" void __cxa_finalize(void *f)
+    {
+        if (!f)
+        {
+            for (std::size_t i = aux::destructor_count; i > 0; --i)
+            {
+                if (aux::destructors[i - 1].func)
+                    (*aux::destructors[i - 1].func)(aux::destructors[i - 1].ptr);
+            }
+        }
+        else
+        {
+            for (std::size_t i = aux::destructor_count; i > 0; --i)
+            {
+                if (aux::destructors[i - 1].func == f)
+                {
+                    (*aux::destructors[i - 1].func)(aux::destructors[i - 1].ptr);
+                    aux::destructors[i - 1].func = nullptr;
+                    aux::destructors[i - 1].ptr = nullptr;
+                    aux::destructors[i - 1].dso = nullptr;
+                    // TODO: shift and decrement count
+                }
+            }
+        }
+    }
 
     __fundamental_type_info::~__fundamental_type_info()

uspace/lib/cpp/src/internal/unwind.cpp

@@ -219 +219 @@
         // TODO: implement
     }
+
+    extern "C" void __cxa_throw_bad_array_new_length()
+    {
+        // TODO: implement
+    }
 }