better error handling

1 files changed, 45 insertions, 34 deletions

diff --git a/src/emitc.c b/src/emitc.c
index bf79a47..e200ce5 100644
--- a/src/emitc.c
+++ b/src/emitc.c
@@ -13,14 +13,15 @@ struct var_t {
     bool constant;
 };
 
-int file_des, out_fd;
-unsigned current_line, num_lines;
+static int file_des, out_fd;
+static unsigned current_line, num_lines;
 
-off_t *line_offset;
+static off_t *line_offset;
 
-bool want_quit;
-int repeats_left;
-imm_t repeat_line;
+static bool want_quit;
+static int repeats_left;
+static imm_t repeat_line;
+static jmp_buf exit_point;
 
 static void error(const char *fmt, ...) __attribute__((noreturn,format(print,1,2)));
 static void vid_write(const char *str);
@@ -138,7 +139,7 @@ static void __attribute__((noreturn,format(printf,1,2))) error(const char *fmt,
     vid_writef("ERROR: %s\n",  fmtbuf);
     va_end(ap);
 
-    exit(EXIT_FAILURE);
+    longjmp(exit_point, 1);
 }
 
 static void __attribute__((format(printf,1,2))) warning(const char *fmt, ...)
@@ -762,22 +763,8 @@ static void (*instr_tab[0x100])(void) = {
     inc_line_pointer,  /*  0xff  */
 };
 
-void ducky_to_c(int fd, int out)
+void write_stub_code(int num_lines)
 {
-    file_des = fd;
-    out_fd = out;
-
-    init_globals();
-
-    if(read_imm() != DUCKY_MAGIC)
-        error("unknown format");
-
-    num_lines = read_imm();
-    for(unsigned int i = 1; i <= num_lines; ++i)
-    {
-        read_imm();
-    }
-
     write_src("/* generated by ducky */\n\n");
 
     write_src("#include <stdarg.h>\n");
@@ -875,7 +862,6 @@ void ducky_to_c(int fd, int out)
     write_src("{\n");
     write_src("/* this uses labels as values, a GCC extension */\n");
 
-
     write_src("const void *jump_table[%d] = ", num_lines + 1);
     write_src("{\n");
     write_src("NULL,\n");
@@ -885,18 +871,43 @@ void ducky_to_c(int fd, int out)
     }
     write_src("};\n");
     write_src_noindent("\n");
+}
 
-    /* and... compile! */
-    while(!want_quit)
+int ducky_to_c(int fd, int out)
+{
+    if(!setjmp(exit_point))
     {
-        instr_t instr = read_instr();
-        if(want_quit)
-            break;
-        void (*handler)(void) = instr_tab[instr];
-        if(handler)
-            handler();
-        else
-            error("invalid instruction %d", instr);
+        file_des = fd;
+        out_fd = out;
+
+        init_globals();
+
+        if(read_imm() != DUCKY_MAGIC)
+            error("unknown format");
+
+        num_lines = read_imm();
+        for(unsigned int i = 1; i <= num_lines; ++i)
+        {
+            read_imm();
+        }
+
+        write_stub_code(num_lines);
+
+        /* and... compile! */
+        while(!want_quit)
+        {
+            instr_t instr = read_instr();
+            if(want_quit)
+                break;
+            void (*handler)(void) = instr_tab[instr];
+            if(handler)
+                handler();
+            else
+                error("invalid instruction %d", instr);
+        }
+        write_src("}\n");
+        return 0;
     }
-    write_src("}\n");
+    else
+        return 1;
 }