]> granicus.if.org Git - strace/blobdiff - unwind.c
Fix preprocessor indentation
[strace] / unwind.c
index c8a0087eb2b4cfb3f86e939147f0246955f16f29..42e6a7fa451ee338ffed1070248372f6557ebffb 100644 (file)
--- a/unwind.c
+++ b/unwind.c
@@ -2,32 +2,11 @@
  * Copyright (c) 2013 Luca Clementi <luca.clementi@gmail.com>
  * Copyright (c) 2013-2018 The strace developers.
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. The name of the author may not be used to endorse or promote products
- *    derived from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * SPDX-License-Identifier: LGPL-2.1-or-later
  */
 
 #include "defs.h"
-#include "mmap_cache.h"
-#include <libunwind-ptrace.h>
+#include "unwind.h"
 
 #ifdef USE_DEMANGLE
 # if defined HAVE_DEMANGLE_H
 # endif
 #endif
 
-/*
- * Type used in stacktrace walker
- */
-typedef void (*call_action_fn)(void *data,
-                              const char *binary_filename,
-                              const char *symbol_name,
-                              unw_word_t function_offset,
-                              unsigned long true_offset);
-typedef void (*error_action_fn)(void *data,
-                               const char *error,
-                               unsigned long true_offset);
-
 /*
  * Type used in stacktrace capturing
  */
@@ -64,158 +31,42 @@ struct unwind_queue_t {
 
 static void queue_print(struct unwind_queue_t *queue);
 
-static unw_addr_space_t libunwind_as;
-
 static const char asprintf_error_str[] = "???";
 
 void
 unwind_init(void)
 {
-       libunwind_as = unw_create_addr_space(&_UPT_accessors, 0);
-       if (!libunwind_as)
-               error_msg_and_die("failed to create address space for stack tracing");
-       unw_set_caching_policy(libunwind_as, UNW_CACHE_GLOBAL);
-       mmap_cache_enable();
+       if (unwinder.init)
+               unwinder.init();
 }
 
 void
 unwind_tcb_init(struct tcb *tcp)
 {
-       if (tcp->unwind_ctx)
+       if (tcp->unwind_queue)
                return;
 
-       tcp->unwind_ctx = _UPT_create(tcp->pid);
-       if (!tcp->unwind_ctx)
-               perror_msg_and_die("_UPT_create");
-
        tcp->unwind_queue = xmalloc(sizeof(*tcp->unwind_queue));
        tcp->unwind_queue->head = NULL;
        tcp->unwind_queue->tail = NULL;
+
+       tcp->unwind_ctx = unwinder.tcb_init(tcp);
 }
 
 void
 unwind_tcb_fin(struct tcb *tcp)
 {
+       if (!tcp->unwind_queue)
+               return;
+
        queue_print(tcp->unwind_queue);
        free(tcp->unwind_queue);
        tcp->unwind_queue = NULL;
 
-       _UPT_destroy(tcp->unwind_ctx);
+       unwinder.tcb_fin(tcp);
        tcp->unwind_ctx = NULL;
 }
 
-static void
-get_symbol_name(unw_cursor_t *cursor, char **name,
-               size_t *size, unw_word_t *offset)
-{
-       for (;;) {
-               int rc = unw_get_proc_name(cursor, *name, *size, offset);
-               if (rc == 0)
-                       break;
-               if (rc != -UNW_ENOMEM) {
-                       **name = '\0';
-                       *offset = 0;
-                       break;
-               }
-               *name = xgrowarray(*name, size, 1);
-       }
-}
-
-static int
-print_stack_frame(struct tcb *tcp,
-                 call_action_fn call_action,
-                 error_action_fn error_action,
-                 void *data,
-                 unw_cursor_t *cursor,
-                 char **symbol_name,
-                 size_t *symbol_name_size)
-{
-       unw_word_t ip;
-       struct mmap_cache_t *cur_mmap_cache;
-
-       if (unw_get_reg(cursor, UNW_REG_IP, &ip) < 0) {
-               perror_msg("Can't walk the stack of process %d", tcp->pid);
-               return -1;
-       }
-
-       cur_mmap_cache = mmap_cache_search(tcp, ip);
-       if (cur_mmap_cache
-           /* ignore mappings that have no PROT_EXEC bit set */
-           && (cur_mmap_cache->protections & MMAP_CACHE_PROT_EXECUTABLE)) {
-               unsigned long true_offset;
-               unw_word_t function_offset;
-
-               get_symbol_name(cursor, symbol_name, symbol_name_size,
-                               &function_offset);
-               true_offset = ip - cur_mmap_cache->start_addr +
-                       cur_mmap_cache->mmap_offset;
-#ifdef USE_DEMANGLE
-               char *demangled_name =
-                       cplus_demangle(*symbol_name,
-                                      DMGL_AUTO | DMGL_PARAMS);
-#endif
-               call_action(data,
-                           cur_mmap_cache->binary_filename,
-#ifdef USE_DEMANGLE
-                           demangled_name ? demangled_name :
-#endif
-                           *symbol_name,
-                           function_offset,
-                           true_offset);
-#ifdef USE_DEMANGLE
-               free(demangled_name);
-#endif
-
-               return 0;
-       }
-
-       /*
-        * there is a bug in libunwind >= 1.0
-        * after a set_tid_address syscall
-        * unw_get_reg returns IP == 0
-        */
-       if (ip)
-               error_action(data, "unexpected_backtracing_error", ip);
-       return -1;
-}
-
-/*
- * walking the stack
- */
-static void
-stacktrace_walk(struct tcb *tcp,
-               call_action_fn call_action,
-               error_action_fn error_action,
-               void *data)
-{
-       char *symbol_name;
-       size_t symbol_name_size = 40;
-       unw_cursor_t cursor;
-       int stack_depth;
-
-       if (!tcp->mmap_cache)
-               error_msg_and_die("bug: mmap_cache is NULL");
-       if (tcp->mmap_cache_size == 0)
-               error_msg_and_die("bug: mmap_cache is empty");
-
-       symbol_name = xmalloc(symbol_name_size);
-
-       if (unw_init_remote(&cursor, libunwind_as, tcp->unwind_ctx) < 0)
-               perror_msg_and_die("Can't initiate libunwind");
-
-       for (stack_depth = 0; stack_depth < 256; ++stack_depth) {
-               if (print_stack_frame(tcp, call_action, error_action, data,
-                               &cursor, &symbol_name, &symbol_name_size) < 0)
-                       break;
-               if (unw_step(&cursor) <= 0)
-                       break;
-       }
-       if (stack_depth >= 256)
-               error_action(data, "too many stack frames", 0);
-
-       free(symbol_name);
-}
-
 /*
  * printing an entry in stack to stream or buffer
  */
@@ -228,10 +79,10 @@ stacktrace_walk(struct tcb *tcp,
  * /lib64/libc.so.6(__libc_start_main+0xed) [0x7fa2f8a5976d]
  * ./a.out() [0x400569]
  */
-#define STACK_ENTRY_SYMBOL_FMT                 \
+#define STACK_ENTRY_SYMBOL_FMT(SYM)            \
        " > %s(%s+0x%lx) [0x%lx]\n",            \
        binary_filename,                        \
-       symbol_name,                            \
+       (SYM),                                  \
        (unsigned long) function_offset,        \
        true_offset
 #define STACK_ENTRY_NOSYMBOL_FMT               \
@@ -248,11 +99,24 @@ static void
 print_call_cb(void *dummy,
              const char *binary_filename,
              const char *symbol_name,
-             unw_word_t function_offset,
+             unwind_function_offset_t function_offset,
              unsigned long true_offset)
 {
-       if (symbol_name && (symbol_name[0] != '\0'))
-               tprintf(STACK_ENTRY_SYMBOL_FMT);
+       if (symbol_name && (symbol_name[0] != '\0')) {
+#ifdef USE_DEMANGLE
+               char *demangled_name =
+                       cplus_demangle(symbol_name,
+                                      DMGL_AUTO | DMGL_PARAMS);
+#endif
+               tprintf(STACK_ENTRY_SYMBOL_FMT(
+#ifdef USE_DEMANGLE
+                                              demangled_name ? demangled_name :
+#endif
+                                              symbol_name));
+#ifdef USE_DEMANGLE
+               free(demangled_name);
+#endif
+       }
        else if (binary_filename)
                tprintf(STACK_ENTRY_NOSYMBOL_FMT);
        else
@@ -277,15 +141,29 @@ print_error_cb(void *dummy,
 static char *
 sprint_call_or_error(const char *binary_filename,
                     const char *symbol_name,
-                    unw_word_t function_offset,
+                    unwind_function_offset_t function_offset,
                     unsigned long true_offset,
                     const char *error)
 {
        char *output_line = NULL;
        int n;
 
-       if (symbol_name)
-               n = asprintf(&output_line, STACK_ENTRY_SYMBOL_FMT);
+       if (symbol_name) {
+#ifdef USE_DEMANGLE
+               char *demangled_name =
+                       cplus_demangle(symbol_name,
+                                      DMGL_AUTO | DMGL_PARAMS);
+#endif
+               n = asprintf(&output_line,
+                            STACK_ENTRY_SYMBOL_FMT(
+#ifdef USE_DEMANGLE
+                                                   demangled_name ? demangled_name :
+#endif
+                                                   symbol_name));
+#ifdef USE_DEMANGLE
+               free(demangled_name);
+#endif
+       }
        else if (binary_filename)
                n = asprintf(&output_line, STACK_ENTRY_NOSYMBOL_FMT);
        else if (error)
@@ -310,7 +188,7 @@ static void
 queue_put(struct unwind_queue_t *queue,
          const char *binary_filename,
          const char *symbol_name,
-         unw_word_t function_offset,
+         unwind_function_offset_t function_offset,
          unsigned long true_offset,
          const char *error)
 {
@@ -337,7 +215,7 @@ static void
 queue_put_call(void *queue,
               const char *binary_filename,
               const char *symbol_name,
-              unw_word_t function_offset,
+              unwind_function_offset_t function_offset,
               unsigned long true_offset)
 {
        queue_put(queue,
@@ -396,19 +274,8 @@ unwind_tcb_print(struct tcb *tcp)
                debug_func_msg("head: tcp=%p, queue=%p",
                               tcp, tcp->unwind_queue->head);
                queue_print(tcp->unwind_queue);
-       } else switch (mmap_cache_rebuild_if_invalid(tcp, __func__)) {
-               case MMAP_CACHE_REBUILD_RENEWED:
-                       unw_flush_cache(libunwind_as, 0, 0);
-                       ATTRIBUTE_FALLTHROUGH;
-               case MMAP_CACHE_REBUILD_READY:
-                       debug_func_msg("walk: tcp=%p, queue=%p",
-                                      tcp, tcp->unwind_queue->head);
-                       stacktrace_walk(tcp, print_call_cb, print_error_cb, NULL);
-                       break;
-               default:
-                       /* Do nothing */
-                       ;
-       }
+       } else
+               unwinder.tcb_walk(tcp, print_call_cb, print_error_cb, NULL);
 }
 
 /*
@@ -425,19 +292,10 @@ unwind_tcb_capture(struct tcb *tcp)
 #endif
        if (tcp->unwind_queue->head)
                error_msg_and_die("bug: unprinted entries in queue");
-
-       switch (mmap_cache_rebuild_if_invalid(tcp, __func__)) {
-       case MMAP_CACHE_REBUILD_RENEWED:
-               unw_flush_cache(libunwind_as, 0, 0);
-               ATTRIBUTE_FALLTHROUGH;
-       case MMAP_CACHE_REBUILD_READY:
-               stacktrace_walk(tcp, queue_put_call, queue_put_error,
-                               tcp->unwind_queue);
-               debug_func_msg("tcp=%p, queue=%p",
+       else {
+               debug_func_msg("walk: tcp=%p, queue=%p",
                               tcp, tcp->unwind_queue->head);
-               break;
-       default:
-               /* Do nothing */
-               ;
+               unwinder.tcb_walk(tcp, queue_put_call, queue_put_error,
+                                 tcp->unwind_queue);
        }
 }