When saving a schematic issue a warning if disk file has been changed since opening

src/editprop.c

@@ -373,6 +373,7 @@ char *strtoupper(char* s) {
   return s;
 }
 
+/* call hash_all_names() (once) before (repeatedly) using this function */
 void set_inst_prop(int i)
 {
   char *ptr;

src/save.c

@@ -928,8 +928,9 @@ void make_symbol(void)
 void make_schematic(const char *schname)
 {
   FILE *fd=NULL;
+
   rebuild_selected_array();
-  if (!xctx->lastsel)  return;
+  if(!xctx->lastsel)  return;
   if (!(fd = fopen(schname, "w")))
   {
     fprintf(errfp, "make_schematic(): problems opening file %s \n", schname);
@@ -965,6 +966,7 @@ int save_schematic(const char *schname) /* 20171020 added return value */
   FILE *fd;
   char name[PATH_MAX]; /* overflow safe 20161122 */
   char *top_path;
+  struct stat buf;
 
   top_path =  xctx->top_path[0] ? xctx->top_path : ".";
 
@@ -978,6 +980,17 @@ int save_schematic(const char *schname) /* 20171020 added return value */
     Tcl_VarEval(interp, "wm title ", top_path, " \"xschem - [file tail [xschem get schname]]\"", NULL);
     Tcl_VarEval(interp, "wm iconname ", top_path, " \"xschem - [file tail [xschem get schname]]\"", NULL);
   }
+
+  if(!stat(name, &buf)) {
+    if(xctx->time_last_modify && xctx->time_last_modify != buf.st_mtime) {
+      Tcl_VarEval(interp, "ask_save \"Schematic file: ", name,
+          " has been changed since opening.\nSave anyway?\" 0", NULL);
+      if(strcmp(tclresult(), "yes") ) {
+        return -1;
+      }
+    }
+  }
+
   if(!(fd=fopen(name,"w")))
   {
     fprintf(errfp, "save_schematic(): problems opening file %s \n",name);
@@ -987,6 +1000,10 @@ int save_schematic(const char *schname) /* 20171020 added return value */
   unselect_all();
   write_xschem_file(fd);
   fclose(fd);
+  /* update time stamp */
+  if(!stat(name)) {
+    xctx->time_last_modify =  buf.st_mtime;
+  }
   my_strncpy(xctx->current_name, rel_sym_path(name), S(xctx->current_name));
   /* <<<<< >>>> why clear all these? */
   xctx->prep_hi_structs=0;
@@ -1058,6 +1075,12 @@ void load_schematic(int load_symbols, const char *filename, int reset_undo) /* 2
     dbg(1, "load_schematic(): opening file for loading:%s, filename=%s\n", name, filename);
     dbg(1, "load_schematic(): sch[currsch]=%s\n", xctx->sch[xctx->currsch]);
     if(!name[0]) return;
+
+    if(!stat(name, &buf)) { /* file exists */
+      xctx->time_last_modify =  buf.st_mtime;
+    } else {
+      xctx->time_last_modify = 0;
+    }
     if( (fd=fopen(name,fopen_read_mode))== NULL) {
       fprintf(errfp, "load_schematic(): unable to open file: %s, filename=%s\n",
           name, filename ? filename : "<NULL>");
@@ -2208,7 +2231,6 @@ void create_sch_from_sym(void)
   char *dir = NULL;
   char *prop = NULL;
   char schname[PATH_MAX];
-  char *savecmd=NULL;
   char *sub_prop;
   char *sub2_prop=NULL;
   char *str=NULL;
@@ -2235,12 +2257,9 @@ void create_sch_from_sym(void)
       my_strncpy(schname, add_ext(abs_sym_path(xctx->inst[xctx->sel_array[0].n].name, ""), ".sch"), S(schname));
     }
     if( !stat(schname, &buf) ) {
-      my_strdup(353, &savecmd, "ask_save \" create schematic file: ");
+      Tcl_VarEval(interp, "ask_save \"Create schematic file: ", schname,
-      my_strcat(354, &savecmd, schname);
+          "?\nWARNING: This schematic file already exists, it will be overwritten\"", NULL);
-      my_strcat(355, &savecmd, " ?\nWARNING: This schematic file already exists, it will be overwritten\"");
-      tcleval(savecmd);
       if(strcmp(tclresult(), "yes") ) {
-        my_free(914, &savecmd);
         return;
       }
     }
@@ -2248,7 +2267,6 @@ void create_sch_from_sym(void)
     {
       fprintf(errfp, "create_sch_from_sym(): problems opening file %s \n",schname);
       tcleval("alert_ {file opening for write failed!} {}");
-      my_free(915, &savecmd);
       return;
     }
     fprintf(fd, "v {xschem version=%s file_version=%s}\n", XSCHEM_VERSION, XSCHEM_FILE_VERSION);
@@ -2311,7 +2329,6 @@ void create_sch_from_sym(void)
   } /* if(xctx->lastsel...) */
   my_free(916, &dir);
   my_free(917, &prop);
-  my_free(918, &savecmd);
   my_free(919, &sub2_prop);
   my_free(920, &str);
 }

src/token.c

@@ -32,7 +32,7 @@ struct inst_hashentry {
                  };
 
 
-static struct inst_hashentry *table[HASHSIZE];
+static struct inst_hashentry *table[HASHSIZE]; /* safe with multiple schematics, hash rebuilt before usage */
 
 enum status {TOK_BEGIN, TOK_TOKEN, TOK_SEP, TOK_VALUE, TOK_END, TOK_ENDTOK};
 
@@ -670,7 +670,7 @@ void new_prop_string(int i, const char *old_prop, int fast, int dis_uniq_names)
  const char *tmp;
  const char *tmp2;
  int q,qq;
- static int last[256];
+ static int last[256]; /* safe to keep with multiple schematics, reset on 1st invocation */
  int old_name_len;
  int new_name_len;
  int n;
@@ -1690,8 +1690,7 @@ int print_spice_element(FILE *fd, int inst)
           /* fputs(value,fd); */
         }
       }
-      else if (strcmp(token,"@symname")==0) /* of course symname must not be present  */
+      else if (strcmp(token,"@symname")==0) /* of course symname must not be present in attributes */
-                                            /* in hash table */
       {
         const char *s = skip_dir(xctx->inst[inst].name);
         tmp = strlen(s) +100 ; /* always make room for some extra chars 
@@ -1700,8 +1699,7 @@ int print_spice_element(FILE *fd, int inst)
         result_pos += my_snprintf(result + result_pos, tmp, "%s", s);
         /* fputs(s,fd); */
       }
-      else if (strcmp(token,"@symname_ext")==0) /* of course symname must not be present  */
+      else if (strcmp(token,"@symname_ext")==0) /* of course symname must not be present in attributes */
-                                            /* in hash table */
       {
         const char *s = get_cell_w_ext(xctx->inst[inst].name, 0);
         tmp = strlen(s) +100 ; /* always make room for some extra chars 
@@ -1710,8 +1708,7 @@ int print_spice_element(FILE *fd, int inst)
         result_pos += my_snprintf(result + result_pos, tmp, "%s", s);
         /* fputs(s,fd); */
       }
-      else if(strcmp(token,"@schname")==0) /* of course schname must not be present  */
+      else if(strcmp(token,"@schname")==0) /* of course schname must not be present in attributes */
-                                           /* in hash table */
       {
         tmp = strlen(xctx->current_name) +100 ; /* always make room for some extra chars 
                                                 * so 1-char writes to result do not need reallocs */
@@ -1720,8 +1717,8 @@ int print_spice_element(FILE *fd, int inst)
         /* fputs(xctx->current_name, fd); */
 
       }
-      else if(strcmp(token,"@pinlist")==0) /* of course pinlist must not be present  */
+      else if(strcmp(token,"@pinlist")==0) /* of course pinlist must not be present in attributes */
-                                           /* in hash table. print multiplicity */
+                                           /* print multiplicity */
       {                                    /* and node number: m1 n1 m2 n2 .... */
         for(i=0;i<no_of_pins;i++)
         {
@@ -2758,7 +2755,7 @@ const char *find_nth(const char *str, char sep, int n)
 const char *translate(int inst, const char* s)
 {
  static const char empty[]="";
- static char *result=NULL;
+ static char *result=NULL; /* safe to keep even with multiple schematics */
  int size=0, tmp;
  register int c, state=TOK_BEGIN, space;
  char *token=NULL;

src/xinit.c

@@ -584,6 +584,7 @@ void alloc_xschem_data(const char *top_path)
   #ifdef IN_MEMORY_UNDO
   xctx->initialized = 0; /* in_memory_undo */
   #endif
+  xctx->time_last_modify = 0;
 }
 
 void delete_schematic_data(void)

src/xschem.h

@@ -709,6 +709,7 @@ typedef struct {
   int *fill_type; /* for every layer: 0: no fill, 1, solid fill, 2: stipple fill */
   int fill_pattern;
   int draw_window; 
+  time_t time_last_modify;
 } Xschem_ctx;
 
 struct Lcc { /* used for symbols containing schematics as instances (LCC, Local Custom Cell) */

src/xschem.tcl

@@ -2270,7 +2270,7 @@ proc attach_labels_to_inst {} {
   return {}
 }
 
-proc ask_save { {ask {save file?}} } {
+proc ask_save { {ask {save file?}} {cancel 1}} {
   global rcode wm_fix
   set rcode {}
   if { [winfo exists .dialog] } return
@@ -2290,10 +2290,12 @@ proc ask_save { {ask {save file?}} } {
    set rcode {yes}
    destroy .dialog
   }
-  button .dialog.f1.b2 -text {Cancel} -command\
+  if {$cancel} {
-  {
+    button .dialog.f1.b2 -text {Cancel} -command\
-   set rcode {}
+    {
-   destroy .dialog
+     set rcode {}
+     destroy .dialog
+    }
   }
   button .dialog.f1.b3 -text {No} -command\
   {
@@ -2301,8 +2303,14 @@ proc ask_save { {ask {save file?}} } {
    destroy .dialog
   }
   pack .dialog.l1 .dialog.f1 -side top -fill x
-  pack .dialog.f1.b1 .dialog.f1.b2 .dialog.f1.b3 -side left -fill x -expand yes
+  pack .dialog.f1.b1 -side left -fill x -expand yes
-  bind .dialog <Escape> {.dialog.f1.b2 invoke}
+  if { $cancel} {
+    pack .dialog.f1.b2 -side left -fill x -expand yes
+  }
+  pack .dialog.f1.b3 -side left -fill x -expand yes
+  if {$cancel} {
+    bind .dialog <Escape> {.dialog.f1.b2 invoke}
+  }
   # needed, otherwise problems when descending with double clixk 23012004
   tkwait visibility .dialog
   grab set .dialog