Move and implement frame buffer functionality

Author: Rot127

contrib/plugins/bap-tracing/frame.c

@@ -0,0 +1,74 @@
+// SPDX-FileCopyrightText: 2025 Rot127 <[email protected]>
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "frame_buffer.h"
+
+static Frame *frame_new_std(uint64_t addr, int vcpu_id) {
+  Frame *frame = g_new(Frame, 1);
+  frame__init(frame);
+
+  StdFrame *sframe = g_new(StdFrame, 1);
+  std_frame__init(sframe);
+  frame->std_frame = sframe;
+
+  sframe->address = addr;
+  sframe->thread_id = vcpu_id;
+
+  OperandValueList *ol_in = g_new(OperandValueList, 1);
+  operand_value_list__init(ol_in);
+  ol_in->n_elem = 0;
+  sframe->operand_pre_list = ol_in;
+
+  OperandValueList *ol_out = g_new(OperandValueList, 1);
+  operand_value_list__init(ol_out);
+  ol_out->n_elem = 0;
+  sframe->operand_post_list = ol_out;
+  return frame;
+}
+
+static void frame_add_operand(Frame *frame, OperandInfo *oi) {
+  OperandValueList *ol;
+  if (oi->operand_usage->written) {
+    ol = frame->std_frame->operand_post_list;
+  } else {
+    ol = frame->std_frame->operand_pre_list;
+  }
+
+  oi->taint_info = g_new(TaintInfo, 1);
+  taint_info__init(oi->taint_info);
+  oi->taint_info->no_taint = 1;
+  oi->taint_info->has_no_taint = 1;
+
+  ol->n_elem += 1;
+  ol->elem = g_renew(OperandInfo *, ol->elem, ol->n_elem);
+  ol->elem[ol->n_elem - 1] = oi;
+}
+
+FrameBuffer *frame_buffer_new(size_t size) {
+  FrameBuffer *fb = g_malloc0(sizeof(FrameBuffer));
+  fb->fbuf = g_malloc0(sizeof(Frame *) * size);
+  fb->max_size = size;
+  return fb;
+}
+
+bool frame_buffer_is_full(const FrameBuffer *buf) {
+  return buf->idx >= buf->max_size;
+}
+
+void frame_buffer_flush_to_file(FrameBuffer *buf, FILE *file);
+
+StdFrame *frame_buffer_new_frame_std(FrameBuffer *buf) {
+  if (frame_buffer_is_full(buf)) {
+    return NULL;
+  }
+  Frame *frame = frame_new_std(0, -1);
+  frame__init(frame);
+
+  StdFrame *sframe = g_new(StdFrame, 1);
+  std_frame__init(sframe);
+  frame->std_frame = sframe;
+  buf->fbuf[buf->idx++] = frame;
+  return sframe;
+}
+
+void frame_buffer_append_op_info(FrameBuffer *buf, OperandInfo *oi);

contrib/plugins/bap-tracing/frame_buffer.c

@@ -0,0 +1,31 @@
+// SPDX-FileCopyrightText: 2025 Rot127 <[email protected]>
+// SPDX-License-Identifier: GPL-2.0-only
+
+#ifndef BAP_FRAME_BUFFER_H
+#define BAP_FRAME_BUFFER_H
+
+#include <qemu-plugin.h>
+#include <stdio.h>
+#include <glib.h>
+
+#include "frame.piqi.pb-c-patched.h"
+
+typedef struct {
+  Frame **fbuf; ///< The frames buffered.
+  size_t idx; ///< Points to currently open frame.
+  size_t max_size; ///< Maximum number of elements fbuf can hold.
+} FrameBuffer;
+
+/**
+ * \brief Initializes a frame buffer with space for \p size frames.
+ * Returns the buffer or NULL in case of failure.
+ */
+FrameBuffer *frame_buffer_new(size_t size);
+
+void frame_buffer_flush_to_file(FrameBuffer *buf, FILE *file);
+bool frame_buffer_is_full(const FrameBuffer *buf);
+
+StdFrame *frame_buffer_new_frame_std(FrameBuffer *buf);
+void frame_buffer_append_op_info(FrameBuffer *buf, OperandInfo *oi);
+
+#endif

contrib/plugins/bap-tracing/frame_buffer.h

@@ -34,6 +34,7 @@ dep_libprotobuf = declare_dependency(
 )
 
 bap_tracing_src = files(
+  'frame_buffer.c',
   'tracing.c',
   'tracewrap.c',
 )

contrib/plugins/bap-tracing/meson.build

@@ -49,28 +49,23 @@ static void add_pre_reg_state(VCPU *vcpu, unsigned int vcpu_index,
 
 static void add_new_insn_frame(VCPU *vcpu, unsigned int vcpu_index,
                                FrameBuffer *fbuf, Instruction *insn) {
-  Frame *frame = frame_buffer_new_frame(fbuf);
-  frame__init(frame);
+  StdFrame *stdframe = frame_buffer_new_frame_std(fbuf);
 
-  StdFrame *sframe = g_new(StdFrame, 1);
-  std_frame__init(sframe);
-  frame->std_frame = sframe;
-
-  sframe->thread_id = vcpu_index;
-  sframe->address = insn->vaddr;
-  sframe->rawbytes.len = insn->size;
-  sframe->rawbytes.data = g_malloc(insn->size);
-  memcpy(sframe->rawbytes.data, insn->bytes, insn->size);
+  stdframe->thread_id = vcpu_index;
+  stdframe->address = insn->vaddr;
+  stdframe->rawbytes.len = insn->size;
+  stdframe->rawbytes.data = g_malloc(insn->size);
+  memcpy(stdframe->rawbytes.data, insn->bytes, insn->size);
 
   OperandValueList *ol_in = g_new(OperandValueList, 1);
   operand_value_list__init(ol_in);
   ol_in->n_elem = 0;
-  sframe->operand_pre_list = ol_in;
+  stdframe->operand_pre_list = ol_in;
 
   OperandValueList *ol_out = g_new(OperandValueList, 1);
   operand_value_list__init(ol_out);
   ol_out->n_elem = 0;
-  sframe->operand_post_list = ol_out;
+  stdframe->operand_post_list = ol_out;
 }
 
 static void log_insn_reg_access(unsigned int vcpu_index, void *udata) {
@@ -140,7 +135,7 @@ static void vcpu_init(qemu_plugin_id_t id, unsigned int vcpu_index) {
   VCPU *vcpu = g_malloc0(sizeof(VCPU));
   vcpu->registers = registers_init(vcpu_index);
   g_array_insert_vals(state.vcpus, vcpu_index, &vcpu, 1);
-  FrameBuffer *vcpu_frame_buffer = frame_buffer_init(FRAME_BUFFER_SIZE_DEFAULT);
+  FrameBuffer *vcpu_frame_buffer = frame_buffer_new(FRAME_BUFFER_SIZE_DEFAULT);
   g_ptr_array_insert(state.frame_buffer, vcpu_index, &vcpu_frame_buffer);
 
   g_rw_lock_writer_unlock(&state.frame_buffer_lock);

contrib/plugins/bap-tracing/tracing.c

@@ -6,10 +6,11 @@
 
 #include <qemu-plugin.h>
 #include <stdio.h>
+#include <glib.h>
 
 #include "frame.piqi.pb-c-patched.h"
-#include "glib.h"
 #include "tracewrap.h"
+#include "frame_buffer.h"
 
 QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
 
@@ -25,11 +26,6 @@ typedef enum {
  */
 #define MAX_INSTRUCTION_SIZE 64
 
-typedef struct {
-  Frame **fbuf;
-  size_t len;
-} FrameBuffer;
-
 typedef struct {
   uint8_t bytes[MAX_INSTRUCTION_SIZE]; ///< Instruction bytes.
   size_t size;                         ///< Len of instruction in bytes.
@@ -58,32 +54,6 @@ typedef struct {
 } TraceState;
 
 VCPU *vcpu_new(void);
-
-/**
- * \brief Initializes a frame buffer with space for \p size frames.
- * Returns the buffer or NULL in case of failure.
- */
-FrameBuffer *frame_buffer_init(size_t size);
-
-/**
- * \brief Push a frame into the buffer.
- * Returns true on success. False otherwise.
- */
-bool frame_buffer_push(FrameBuffer *buf, Frame *frame);
-
-void frame_buffer_flush_to_file(FrameBuffer *buf, FILE *file);
-bool frame_buffer_is_full(const FrameBuffer *buf);
-
-Frame *frame_buffer_new_frame(FrameBuffer *buf);
-void frame_buffer_append_op_info(FrameBuffer *buf, OperandInfo *oi);
-
-/**
- * \brief Create new std frame
- */
-Frame *frame_new_std(uint64_t addr, int vcpu_id);
-
-void frame_add_operand(Frame *frame, OperandInfo *oi);
-
 Register *init_vcpu_register(qemu_plugin_reg_descriptor *desc);
 Instruction *init_insn(struct qemu_plugin_insn *insn);