pound: add save file

apps/pound.c

@@ -103,13 +103,80 @@ void editorInsertChar(uint8_t c) {
     editorDrawStatusMsg(OUT_OF_MEMORY_STRING);
 }
 
-// -------------------- FILE INPUT --------------------
+// -------------------- FILE INPUT/OUTPUT --------------------
+
+static inline uint8_t write_byte(FCB *fcb, uint8_t c, uint8_t *opos) {
+    cpm_default_dma[*opos] = c;
+    (*opos)++;
+    if (*opos == 128) {
+        if (cpm_write_sequential(fcb)) return 0xff;
+        *opos = 0;
+    }
+    return 0;
+}
+
+uint8_t write_file(FCB *fcb) {
+    fcb->ex = fcb->s1 = fcb->s2 = fcb->rc = 0;
+    if (cpm_make_file(fcb)) return 0xff;
+    fcb->cr = 0;
+
+    cpm_set_dma(cpm_default_dma);
+
+    uint8_t opos = 0;
+
+    for (int j=0; j<E.numrows; j++) {
+        for (int i=0; i<E.row[j].size; i++) {
+            if (write_byte(fcb, E.row[j].chars[i], &opos)) return 0xff;
+        }
+        if (write_byte(fcb, '\r', &opos)) return 0xff;
+        if (write_byte(fcb, '\n', &opos)) return 0xff;
+    }
+    if (write_byte(fcb, CTRL('Z'), &opos)) return 0xff;
+    if (opos && cpm_write_sequential(fcb)) return 0xff;
+
+    return cpm_close_file(fcb);
+}
+
+void editorSave(void) {
+    cpm_fcb.ex = cpm_fcb.s1 = cpm_fcb.s2 = cpm_fcb.rc = 0;
+
+    if (cpm_open_file(&cpm_fcb)) {
+        editorDrawStatusMsg("Saving to new file...");
+        if (write_file(&cpm_fcb)) editorDrawStatusMsg("Failed to save file");
+        return;
+    }
+
+    editorDrawStatusMsg("Saving to temporary file...");
+
+    static FCB tempfcb;
+    strcpy((char *)tempfcb.f, "POUNDTMP$$$");
+    tempfcb.dr = cpm_fcb.dr;
+    if (write_file(&tempfcb)) {
+        editorDrawStatusMsg("Failed to create temporary file");
+        return;
+    }
+
+    editorDrawStatusMsg("Removing old file...");
+    if (cpm_delete_file(&cpm_fcb)) {
+        editorDrawStatusMsg("Unable to delete old file...");
+        return;
+    }
+
+    editorDrawStatusMsg("Renaming temporary file...");
+    memcpy(((uint8_t*)&tempfcb) + 16, &cpm_fcb, 16);
+    if (cpm_rename_file((RCB*)&tempfcb)) {
+        editorDrawStatusMsg("Renaming failed...");
+        return;
+    }
+
+    editorDrawStatusMsg("File saved");
+}
 
 char line[256];
 
 void editorOpen(void) {
     cpm_fcb.cr = 0;
-    if (cpm_open_file(&cpm_fcb)) die("Unable to read file", false);
+    if (cpm_open_file(&cpm_fcb)) return;    // new file
 
     cpm_set_dma(cpm_default_dma);
 
@@ -265,6 +332,11 @@ void editorProcessKeypress(void) {
         case CTRL('Q'):             // ^KQ Quit
             die("Done.", true);
             break;
+        case 's':
+        case 'S':
+        case CTRL('S'):             // ^KS Save
+            editorSave();
+            break;
         }
         ctrlk = false;
         return;