From a8537ba6d465b00f1ddc3406fcceda45d1759d95 Mon Sep 17 00:00:00 2001
From: Sander Speetjens <sander.speetjens@gmail.com>
Date: Tue, 5 Dec 2023 22:29:15 +0100
Subject: [PATCH] tftp

try to fix a bug Lorenz told me about
in fwrite
---
 project/Core/Src/tftp.c |  8 ++++----
 tests/mocs.c            |  2 +-
 tests/mocs.h            |  2 +-
 tests/tfpt_tests.cpp    | 18 ++++++++++++++++++
 4 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/project/Core/Src/tftp.c b/project/Core/Src/tftp.c
index b19a12e..da67f95 100644
--- a/project/Core/Src/tftp.c
+++ b/project/Core/Src/tftp.c
@@ -100,12 +100,12 @@ size_t tftp_custom_fread(void* buf, size_t bytes, tftp_custom_file_t* handle) {
  * @return The number of bytes written
  */
 size_t tftp_custom_fwrite(const void* buf, size_t bytes, tftp_custom_file_t* handle) {
-    if (handle->offset + bytes > handle->len) {
-        bytes = handle->len - handle->offset;
+    if (handle->offset + bytes >= handle->len) {
+        bytes = handle->len - handle->offset - 1;
     }
     memcpy(handle->data + handle->offset, buf, bytes);
     handle->offset += bytes;
-    if (handle->offset > handle->len) {
+    if (handle->offset >= handle->len) {
         bytes = 0;
     }
     return bytes;
@@ -171,7 +171,7 @@ void tftp_close(void* handle) {
     if (handle == &virt_file[VIRT_TEXT_TXT]) {
         lcd_clear_images();
         lcd_clear_text();
-        lcd_display_text((const char*)virt_file[VIRT_TEXT_TXT].data, 0, 0, LCD_COLOR_WHITE, LCD_TRANSPARENT, LCD_FONT16);
+        lcd_display_text((char*)virt_file[VIRT_TEXT_TXT].data, 0, 0, LCD_COLOR_WHITE, LCD_TRANSPARENT, LCD_FONT16);
     }
 
     if (handle == &virt_file[VIRT_INDEX_TXT] || handle == &virt_file[VIRT_IMAGE_BMP]
diff --git a/tests/mocs.c b/tests/mocs.c
index bceea4e..19db235 100644
--- a/tests/mocs.c
+++ b/tests/mocs.c
@@ -12,7 +12,7 @@ int tftp_init(struct tftp_context* context) {
     return 0;
 }
 
-void lcd_display_text(uint8_t* text, uint16_t x_pos, uint16_t y_pos, uint32_t color, uint32_t bg_color, sFONT* font) {
+void lcd_display_text(const char* text, uint16_t x_pos, uint16_t y_pos, uint32_t color, uint32_t bg_color, sFONT* font) {
     UNUSED(color);
     UNUSED(bg_color);
     UNUSED(font);
diff --git a/tests/mocs.h b/tests/mocs.h
index d978179..b67fab7 100644
--- a/tests/mocs.h
+++ b/tests/mocs.h
@@ -93,7 +93,7 @@ typedef err_t (*tcp_accept_fn)(void *arg, struct tcp_pcb *newpcb, err_t err);
 
 uint32_t logger_get_timestamp(void);
 
-void lcd_display_text(uint8_t* text, uint16_t x_pos, uint16_t y_pos, uint32_t color, uint32_t bg_color, sFONT *font);
+void lcd_display_text(const char* text, uint16_t x_pos, uint16_t y_pos, uint32_t color, uint32_t bg_color, sFONT *font);
 void lcd_draw_img_from_fs(char* filename, uint32_t x_pos, uint32_t y_pos);
 void lcd_draw_gif_from_fs(char* filename, uint32_t x_pos, uint32_t y_pos);
 void lcd_draw_bmp_img(uint8_t* bmp_buff, uint32_t x_pos, uint32_t y_pos);
diff --git a/tests/tfpt_tests.cpp b/tests/tfpt_tests.cpp
index 1fa2d95..597addf 100644
--- a/tests/tfpt_tests.cpp
+++ b/tests/tfpt_tests.cpp
@@ -74,4 +74,22 @@ TEST(TFTP, custom_fwrite) {
     free(write_file.data);
     write_file.data = NULL;
     write_file.len = 0;
+}
+
+TEST(TFTP, custom_fread_fwrite_suggested_by_Lorentz) {
+    write_file.data = (char*)malloc(21 * sizeof(char));
+    write_file.len = 21;
+    write_file.offset = 0;
+    tftp_custom_fwrite("1234567890123456789", 19, &write_file);
+
+    tftp_custom_fwrite("0987654321", 10, &write_file);
+    EXPECT_EQ(write_file.offset, 20);
+    EXPECT_EQ(write_file.len, 21);
+    EXPECT_EQ(memcmp(write_file.data, "12345678901234567890", 20), 0);
+    free(write_file.data);
+
+    char buf[21];
+    file.offset = 9;
+    tftp_custom_fread(buf, 20, &file);
+    EXPECT_EQ(memcmp(buf, "0", 1), 0);
 }
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