implement external interface to library and use it in tests. need to be

reworked a bit to use file descriptor or buffer provided to callse

src/Makefile

@@ -31,7 +31,7 @@ SOFT_BUILD	= $(shell STR=`cat $(BUILD_DIR)/version.h 2> /dev/null | grep 'SOFT_B
 DATE_BUILD	= $(shell date +"%D %T")
 
 #source and header files search path. add here new directories which contains files specified for $(SRC)
-VPATH 		= . dwarf arch utils
+VPATH 		= ./ ./dwarf ./arch ./utils
 
 SRC			= $(wildcard $(addsuffix /*.cpp,${VPATH}))
 OBJ			= $(patsubst %.cpp,%.o,$(addprefix $(BUILD_DIR)/,$(notdir $(SRC))))

src/context.cpp

@@ -151,10 +151,6 @@ bool print_expr_block (pst_context* ctx, Dwarf_Op *exprs, int exprlen, Dwarf_Att
 
 void pst_context_init(pst_context* ctx, ucontext_t* hctx)
 {
-    // global
-    pst_alloc_init(&allocator);
-    pst_log_init_console(&logger);
-
     // methods
     ctx->clean_print = clean_print;
     ctx->print = print;
@@ -184,10 +180,6 @@ void pst_context_fini(pst_context* ctx)
     ctx->frame = NULL;
     ctx->dwfl = NULL;
     ctx->module = NULL;
-
-    // global
-    pst_log_fini(&logger);
-    pst_alloc_fini(&allocator);
 }
 
 

src/libpst.cpp

@@ -0,0 +1,91 @@
+/*
+ * libpst.c
+ *
+ *  Created on: Feb 5, 2020
+ *      Author: nnosov
+ */
+
+#include <ucontext.h>
+#include <stdio.h>
+#include <stdint.h>
+
+#include "utils/allocator.h"
+#include "dwarf/dwarf_handler.h"
+
+// allocate and initialize libpst handler.
+pst_handler* pst_new_handler(ucontext_t* hctx)
+{
+    // global
+    pst_alloc_init(&allocator);
+    pst_log_init_console(&logger);
+
+    pst_new(pst_handler, handler, hctx);
+    return handler;
+}
+
+// deallocate libpst handler
+void pst_del_handler(pst_handler* h)
+{
+    pst_free(h);
+
+    // global
+    pst_log_fini(&logger);
+    pst_alloc_fini(&allocator);
+}
+
+// write stack trace information to provided file descriptor
+int pst_unwind_simple(pst_handler* h, FILE* fd)
+{
+    int ret = pst_handler_unwind(h);
+    if(ret) {
+        fwrite(h->ctx.buff, 1, strlen(h->ctx.buff), fd);
+        return 0;
+    }
+
+    return -1;
+}
+
+// save stack trace information to provided buffer in RAM
+int pst_unwind_simple(pst_handler* h, char* buff, uint32_t buff_size)
+{
+    int ret = pst_handler_unwind(h);
+    if(ret) {
+        uint32_t cnt = buff_size < sizeof(h->ctx.buff) ? buff_size : sizeof(h->ctx.buff);
+        memcpy(buff, h->ctx.buff, cnt - 2);
+        buff[cnt - 1] = 0;
+
+        return 0;
+    }
+
+    return -1;
+}
+
+
+// write stack trace information to provided file descriptor
+int pst_unwind_pretty(pst_handler* h, FILE* fd)
+{
+    int ret = pst_handler_handle_dwarf(h);
+    if(ret) {
+        pst_handler_print_dwarf(h);
+        fwrite(h->ctx.buff, 1, strlen(h->ctx.buff), fd);
+        return 0;
+    }
+
+    return -1;
+}
+
+// save stack trace information to provided buffer in RAM
+int pst_unwind_pretty(pst_handler* h, char* buff, uint32_t buff_size)
+{
+    int ret = pst_handler_handle_dwarf(h);
+    if(ret) {
+        pst_handler_print_dwarf(h);
+        uint32_t cnt = buff_size < sizeof(h->ctx.buff) ? buff_size : sizeof(h->ctx.buff);
+        memcpy(buff, h->ctx.buff, cnt - 2);
+        buff[cnt - 1] = 0;
+
+        return 0;
+    }
+
+    return -1;
+}