Print expanded source

debugus.c

@@ -54,6 +54,51 @@ int msleep(long msec)
 #define INIT_SCRIPT ".debugusrc.js"
 #define MAX_JS_FUNCS 100
 
+void print_source(const char *file, size_t line)
+{
+    FILE *src = fopen(file, "r");
+    if (src == NULL) {
+        LOG_ERR("No source file found\n");
+        return;
+    }
+    fseek(src, 0L, SEEK_END);
+    long sz = ftell(src);
+    rewind(src);
+    
+    char *srcbuf = malloc(sz+1);
+    fread(srcbuf, sz, 1, src);
+    srcbuf[sz] = '\0';                    
+
+    const int expand = 4;
+
+    char *p = srcbuf;
+    size_t i = 0;
+    while (p) {
+        char *next = strchr(p, '\n');
+        if (next) {
+            *next = '\0';
+        }
+
+        int lo = line - expand;
+        int hi = line + expand;
+        if (i >= (lo < 0 ? 0 : lo) && i <= hi ) {
+            char prefix[20];
+            snprintf(prefix, sizeof(prefix), "%2s %6zu", i == line ? "->" : "", i);
+            printf("%s %s\n", prefix, p);
+        }
+
+        if (next) {
+            *next = '\n';
+        }
+
+        p = next ? (next + 1) : NULL;
+        i++;
+    }
+
+    free(srcbuf);
+    fclose(src);
+}
+
 // Registers
 // Taken from da goat https://source.winehq.org/source/dlls/dbghelp/cpu_x86_64.c
 
@@ -219,46 +264,6 @@ void dbg_handle_sigsegv(Dbg *dbg, siginfo_t info)
     }
 }
 
-void print_source(const char *file, size_t line)
-{
-    FILE *src = fopen(file, "r");
-    if (src == NULL) {
-        LOG_ERR("No source file found\n");
-        return;
-    }
-    fseek(src, 0L, SEEK_END);
-    long sz = ftell(src);
-    rewind(src);
-    
-    char *srcbuf = malloc(sz+1);
-    fread(srcbuf, sz, 1, src);
-    srcbuf[sz] = '\0';                    
-
-    char *p = srcbuf;
-    size_t i = 0;
-    while (p) {
-        char *next = strchr(p, '\n');
-        if (next) {
-            *next = '\0';
-        }
-
-        if (i == line) {
-            LOG_INF("Source:\n");
-            printf("%6zu %s\n", line, p);
-        }
-
-        if (next) {
-            *next = '\n';
-        }
-
-        p = next ? (next + 1) : NULL;
-        i++;
-    }
-
-    free(srcbuf);
-    fclose(src);
-}
-
 void dbg_handle_sigtrap(Dbg *dbg, siginfo_t info)
 {
     void dbg_set_rip(Dbg *dbg, uint64_t v);