EDIT: Enhanced file_ui() to support directories bigger than io_buf[]

apps/edit.c

@@ -2028,7 +2028,9 @@ struct tabent {
   uint32_t size;
 } *entry;
 
-#define FILELINES 16
+// It is best if FILESPERPAGE is a multiple of FILELINES
+#define FILELINES 16       // Number of lines displayed in file_ui
+#define FILESPERPAGE 160   // Number of files loaded into iobuf[]
 
 /*
  * Draw one line in file chooser UI
@@ -2133,6 +2135,49 @@ uint16_t online(void) {
   return entries;
 }
 
+/*
+ * Read directory entries and populate table in iobuf[]
+ * for file_ui()
+ * page - page index, each page has FILESPERPAGE entries
+ *        page is 0, 1, 2, 3 ...
+ * num_entries - number of entries read
+ * Returns 0 there are more files, 1 if end of directory reached
+ */
+uint8_t read_dir(uint8_t page, uint16_t *num_entries) {
+  DIR *dp;
+  struct dirent *ent;
+  struct tabent *entry;
+  uint8_t rc = 0;
+  uint16_t entries = 0, i = 0;
+  entry = (struct tabent*)iobuf;
+  if (page == 0) {
+    strcpy(entry->name, ".."); // Add fake '..' entry
+    entry->type = 0x0f;
+    ++entry;
+    ++entries;
+  }
+  dp = opendir(".");
+  while (1) {
+    ent = readdir(dp);
+    if (!ent) {
+      rc = 1;
+      break;
+    }
+    if (++i < page * FILESPERPAGE)
+      continue;
+    if (entries >= FILESPERPAGE)
+      break;
+    memcpy(entry->name, ent->d_name, 16);
+    entry->type = ent->d_type;
+    entry->size = ent->d_size;
+    ++entry;
+    ++entries;
+  }
+  closedir(dp);
+  *num_entries = entries;
+  return rc;
+}
+
 /*
  * File chooser UI
  * Leaves file name in userentry[], or empty string if error/cancel
@@ -2142,13 +2187,15 @@ uint16_t online(void) {
  */
 void file_ui(char *msg1, char *msg2, char *msg3) {
   struct tabent *entry;
-  DIR *dp;
-  struct dirent *ent;
   char c;
-  uint16_t entries, current, first;
-  uint8_t toplevel = 0;
+  uint16_t entries;
+  uint8_t end_of_dir;
+  uint16_t first = 0, current = 0;
+  uint8_t toplevel = 0, page = 0;
+  cutbuflen = 0;
 restart:
   clrscr();
+  cursor(0);
   gotoxy(0,0);
   revers(1);
   cprintf("%s", msg1);
@@ -2162,34 +2209,10 @@ restart:
   revers(1);
   cprintf("%s", (toplevel ? "Volumes" : userentry));
   revers(0);
-  entries = current = first = 0;
-  cutbuflen = 0;
-  if (toplevel) {
+  if (toplevel)
     entries = online();
-  } else {
-    entry = (struct tabent*)iobuf;
-    strcpy(entry->name, ".."); // Add fake '..' entry
-    entry->type = 0x0f;
-    ++entry;
-    ++entries;
-    cursor(0);
-    dp = opendir(".");
-    while (1) {
-      ent = readdir(dp);
-      if (!ent)
-        break;
-      memcpy(entry->name, ent->d_name, 16);
-      entry->type = ent->d_type;
-      entry->size = ent->d_size;
-      ++entry;
-      ++entries;
-      if ((char*)entry > (char*)iobuf + CUTBUFSZ - 100) {
-        beep();
-        break;
-      }
-    }
-    closedir(dp);
-  }
+  else
+    end_of_dir = read_dir(page, &entries);
 redraw:
   file_ui_draw_all(first, current, entries);
   while (1) {
@@ -2198,6 +2221,13 @@ redraw:
     case 0x0b:  // Up
       if (current > 0)
         --current;
+      else
+        if (page > 0) {
+          --page;
+          current = FILESPERPAGE - 1;
+          first = current - FILELINES + 1;
+          goto restart;
+        }
       if (current < first) {
         if (first > FILELINES)
           first -= FILELINES;
@@ -2211,6 +2241,11 @@ redraw:
     case 0x0a:  // Down
       if (current < entries - 1)
         ++current;
+      else if (!end_of_dir) {
+        ++page;
+        first = current = 0;
+        goto restart;
+      }
       if (current >= first + FILELINES) {
         first += FILELINES;
         goto redraw;
@@ -2233,6 +2268,7 @@ redraw:
             toplevel = 1;
           else
             chdir(userentry);
+          first = current = 0;
           goto restart;
         } else {
           if (toplevel) {
@@ -2245,6 +2281,7 @@ redraw:
             chdir(userentry);
           }
           toplevel = 0;
+          first = current = 0;
           goto restart;
         }
         break;