From 515e7be314069d05e855f8abddebe584accaf78b Mon Sep 17 00:00:00 2001
From: tracer-ysyx <tracer@ysyx.org>
Date: Thu, 8 Feb 2024 18:43:12 +0800
Subject: [PATCH] =?UTF-8?q?>=20compile=20NEMU=20ysyx=5F22040000=20?=
 =?UTF-8?q?=E6=9D=8E=E5=BF=83=E6=9D=A8=20Linux=20calcite=206.1.75=20#1-Nix?=
 =?UTF-8?q?OS=20SMP=20PREEMPT=5FDYNAMIC=20Thu=20Jan=2025=2023:27:52=20UTC?=
 =?UTF-8?q?=202024=20x86=5F64=20GNU/Linux=20=2018:43:12=20=20up=201=20day?=
 =?UTF-8?q?=20=204:19,=20=202=20users,=20=20load=20average:=201.84,=201.38?=
 =?UTF-8?q?,=200.75?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 nemu/src/monitor/sdb/sdb.c        |  14 ++++
 nemu/src/monitor/sdb/sdb.h        |   2 +
 nemu/src/monitor/sdb/watchpoint.c | 104 +++++++++++++++---------------
 3 files changed, 68 insertions(+), 52 deletions(-)

diff --git a/nemu/src/monitor/sdb/sdb.c b/nemu/src/monitor/sdb/sdb.c
index 8d4df29..aa646dd 100644
--- a/nemu/src/monitor/sdb/sdb.c
+++ b/nemu/src/monitor/sdb/sdb.c
@@ -32,6 +32,7 @@ static int is_batch_mode = false;
 static int cmd_help(char *args);
 static int cmd_c(char *args);
 static int cmd_q(char *args);
+static int cmd_w(char *args);
 static int cmd_x(char *args);
 static int cmd_si(char *args);
 static int cmd_info(char *args);
@@ -55,6 +56,7 @@ static struct CommandTable {
       {"c", "Continue the execution of the program", cmd_c, NULL, 0},
       {"q", "Exit NEMU", cmd_q, NULL, 0},
       {"x", "Examine content of physical memory address", cmd_x, NULL, 0},
+      {"w", "Break when expression is changed", cmd_w, NULL, 0},
       {"si", "Execute next [n] program line", cmd_si, NULL, 0},
       {"info", "Print information of registers or watchpoints", cmd_info,
        cmd_info_table, ARRLEN(cmd_info_table)},
@@ -181,6 +183,18 @@ static int cmd_info_w(char *args) {
   return 0;
 }
 
+static int cmd_w(char *args) {
+  char *expr = strtok(NULL, " ");
+  bool success = false;
+  parse_expr(expr, &success);
+  if (!success) {
+    Error("Failed to parse given expression %s", expr);
+    return 0;
+  }
+  wp_add(expr);
+  return 0;
+}
+
 static int cmd_x(char *args) {
   char *arg = strtok(NULL, " ");
   bool res = false;
diff --git a/nemu/src/monitor/sdb/sdb.h b/nemu/src/monitor/sdb/sdb.h
index d83d2c6..883f1b6 100644
--- a/nemu/src/monitor/sdb/sdb.h
+++ b/nemu/src/monitor/sdb/sdb.h
@@ -19,5 +19,7 @@
 #include <common.h>
 
 word_t parse_expr(const char *arg, bool *success);
+int wp_add(char * expr);
+int wp_remove_by_number(int number);
 
 #endif
diff --git a/nemu/src/monitor/sdb/watchpoint.c b/nemu/src/monitor/sdb/watchpoint.c
index cbe1b74..bd03030 100644
--- a/nemu/src/monitor/sdb/watchpoint.c
+++ b/nemu/src/monitor/sdb/watchpoint.c
@@ -27,8 +27,8 @@ typedef struct watchpoint {
 } WP;
 
 static WP wp_pool[NR_WP] = {};
-static WP *head = NULL, *free_ = NULL;
-// static int wp_count = 0;
+static WP *head = NULL, *tail = NULL, *free_ = NULL;
+static int wp_count = 0;
 
 void init_wp_pool() {
   int i;
@@ -41,62 +41,62 @@ void init_wp_pool() {
   free_ = wp_pool;
 }
 
-// static WP *wp_new() {
-//   if (free_ == NULL) {
-//     Error("wp_pool: Watchpoint pool not initialized or is full.");
-//     return NULL;
-//   }
+static WP *wp_new() {
+  if (free_ == NULL) {
+    Error("wp_pool: Watchpoint pool not initialized or is full.");
+    return NULL;
+  }
   
-//   WP *ret = free_;
-//   free_ = free_->next;
+  WP *ret = free_;
+  free_ = free_->next;
 
-//   ret->NO = 0;
-//   ret->next = NULL;
-//   return ret;
-// }
+  ret->NO = 0;
+  ret->next = NULL;
+  return ret;
+}
 
-// static void wp_delete(WP *wp) {
-//   assert(wp);
-//   wp->next = free_;
-//   free_ = wp;
-// }
+static void wp_delete(WP *wp) {
+  assert(wp);
+  wp->next = free_;
+  free_ = wp;
+}
 
-// static int wp_add(char * expr) {
-//   WP *wp = wp_new();
-//   if (wp == NULL) {
-//     Error("watchpoint: Failed to add watchpoint, pool is full.");
-//     return 1;
-//   }
+int wp_add(char * expr) {
+  WP *wp = wp_new();
+  if (wp == NULL) {
+    Error("watchpoint: Failed to add watchpoint, pool is full.");
+    return 1;
+  }
 
-//   wp->NO = wp_count++;
-//   if (tail == NULL) {
-//     head = wp;
-//     tail = wp;
-//   } else {
-//     tail->next = wp;
-//     tail = wp;
-//   }
-//   return 0;
-// }
+  wp->NO = wp_count++;
+  if (tail == NULL) {
+    head = wp;
+    tail = wp;
+  } else {
+    tail->next = wp;
+    tail = wp;
+  }
+  return 0;
+}
 
-// static int wp_remove_by_number(int number) {
-//   WP *target_prev;
-//   // Find previous node of target number
-//   for (target_prev = head; target_prev != NULL && target_prev->next->NO != number; target_prev = target_prev->next) ;
-//   if (target_prev == NULL) {
-//     Error("Watchpoint not found, you can check current watchpoints with `info w`");
-//     return 1;
-//   }
-//   WP *target = target_prev->next;
-//   target_prev->next = target->next;
-//   if (target == head) {
-//     head = target->next;
-//   } else if (target == tail) {
-//     tail = target_prev;
-//   }
-//   wp_delete(target);
-//   return 0;
-// }
+int wp_remove_by_number(int number) {
+  WP *target_prev;
+  // Find previous node of target number
+  for (target_prev = head; target_prev != NULL && target_prev->next->NO != number; target_prev = target_prev->next) ;
+  if (target_prev == NULL) {
+    Error("Watchpoint not found, you can check current watchpoints with `info w`");
+    return 1;
+  }
+  WP *target = target_prev->next;
+  target_prev->next = target->next;
+  if (target == head) {
+    head = target->next;
+  } else if (target == tail) {
+    tail = target_prev;
+  }
+  wp_delete(target);
+  return 0;
+}
 
 static bool wp_check_change(WP* wp) {
   bool success = false;