github.com/guyezi/gofrontend@v0.0.0-20200228202240-7a62a49e62c0/libgo/go/runtime/testdata/testprogcgo/tracebackctxt_c.c (about)

     1  // Copyright 2016 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // The C definitions for tracebackctxt.go. That file uses //export so
     6  // it can't put function definitions in the "C" import comment.
     7  
     8  // +build !gccgo
     9  
    10  #include <stdlib.h>
    11  #include <stdint.h>
    12  
    13  // Functions exported from Go.
    14  extern void G1(void);
    15  extern void G2(void);
    16  
    17  void C1() {
    18  	G1();
    19  }
    20  
    21  void C2() {
    22  	G2();
    23  }
    24  
    25  struct cgoContextArg {
    26  	uintptr_t context;
    27  };
    28  
    29  struct cgoTracebackArg {
    30  	uintptr_t  context;
    31  	uintptr_t  sigContext;
    32  	uintptr_t* buf;
    33  	uintptr_t  max;
    34  };
    35  
    36  struct cgoSymbolizerArg {
    37  	uintptr_t   pc;
    38  	const char* file;
    39  	uintptr_t   lineno;
    40  	const char* func;
    41  	uintptr_t   entry;
    42  	uintptr_t   more;
    43  	uintptr_t   data;
    44  };
    45  
    46  // Uses atomic adds and subtracts to catch the possibility of
    47  // erroneous calls from multiple threads; that should be impossible in
    48  // this test case, but we check just in case.
    49  static int contextCount;
    50  
    51  int getContextCount() {
    52  	return __atomic_load_n(&contextCount, __ATOMIC_SEQ_CST);
    53  }
    54  
    55  void tcContext(void* parg) {
    56  	struct cgoContextArg* arg = (struct cgoContextArg*)(parg);
    57  	if (arg->context == 0) {
    58  		arg->context = __atomic_add_fetch(&contextCount, 1, __ATOMIC_SEQ_CST);
    59  	} else {
    60  		if (arg->context != __atomic_load_n(&contextCount, __ATOMIC_SEQ_CST))
    61  			abort();
    62  		}
    63  		__atomic_sub_fetch(&contextCount, 1, __ATOMIC_SEQ_CST);
    64  	}
    65  }
    66  
    67  void tcTraceback(void* parg) {
    68  	int base, i;
    69  	struct cgoTracebackArg* arg = (struct cgoTracebackArg*)(parg);
    70  	if (arg->context == 0) {
    71  		// This shouldn't happen in this program.
    72  		abort();
    73  	}
    74  	// Return a variable number of PC values.
    75  	base = arg->context << 8;
    76  	for (i = 0; i < arg->context; i++) {
    77  		if (i < arg->max) {
    78  			arg->buf[i] = base + i;
    79  		}
    80  	}
    81  }
    82  
    83  void tcSymbolizer(void *parg) {
    84  	struct cgoSymbolizerArg* arg = (struct cgoSymbolizerArg*)(parg);
    85  	if (arg->pc == 0) {
    86  		return;
    87  	}
    88  	// Report two lines per PC returned by traceback, to test more handling.
    89  	arg->more = arg->file == NULL;
    90  	arg->file = "tracebackctxt.go";
    91  	arg->func = "cFunction";
    92  	arg->lineno = arg->pc + (arg->more << 16);
    93  }