Correctly handle cases where files already exist on the filesystem.

Also: patched a bug wherein the filename filter was acting up, transforming `file.zip` to `file-zip.zip`, for example.

include/fs.h

@@ -44,5 +44,6 @@ u32 compress_lz_file_fast(FS_Path path, FS_Archive archive, char *in_buf, u32 si
 
 Result buf_to_file(u32 size, FS_Path path, FS_Archive archive, char *buf);
 void remake_file(FS_Path path, FS_Archive archive, u32 size);
+void save_zip_to_sd(char * filename, u32 size, char * buf, EntryMode mode);
 
 #endif

source/camera.c

@@ -391,14 +391,7 @@ bool init_qr(void)
 
                 if(mode != MODE_AMOUNT)
                 {
-                    char path_to_file[0x107] = {0};
+                    save_zip_to_sd(filename, zip_size, zip_buf, mode);
-                    sprintf(path_to_file, "%s%s", main_paths[mode], filename);
-                    char * extension = strrchr(path_to_file, '.');
-                    if (extension == NULL || strcmp(extension, ".zip"))
-                        strcat(path_to_file, ".zip");
-
-                    remake_file(fsMakePath(PATH_ASCII, path_to_file), ArchiveSD, zip_size);
-                    buf_to_file(zip_size, fsMakePath(PATH_ASCII, path_to_file), ArchiveSD, zip_buf);
                     success = true;
                 }
                 else

source/fs.c

@@ -27,6 +27,7 @@
 #include <strings.h>
 
 #include "fs.h"
+#include "draw.h"
 #include "unicode.h"
 
 #include <archive.h>
@@ -351,3 +352,116 @@ void remake_file(FS_Path path, FS_Archive archive, u32 size)
     buf_to_file(size, path, archive, buf);
     free(buf);
 }
+
+#define ILLEGAL_CHARS "><\"?;:/\\+,.|[=]"
+static SwkbdCallbackResult fat32filter(void *user, const char **ppMessage, const char *text, size_t textlen)
+{
+    (void)textlen;
+    (void)user;
+    *ppMessage = "Input must not contain:\n" ILLEGAL_CHARS;
+    if(strpbrk(text, ILLEGAL_CHARS))
+    {
+        DEBUG("illegal filename: %s\n", text);
+        return SWKBD_CALLBACK_CONTINUE;
+    }
+
+    return SWKBD_CALLBACK_OK;
+}
+
+// assumes the input buffer is a ZIP. if it isn't, why are you calling this?
+void save_zip_to_sd(char * filename, u32 size, char * buf, EntryMode mode)
+{
+    static char path_to_file[32761]; // FAT32 paths can be quite long.
+    const int max_chars = 250;
+    char new_filename[max_chars + 5]; // .zip + \0
+renamed:
+    sprintf(path_to_file, "%s%s", main_paths[mode], filename);
+
+    // filter out characters illegal in FAT32 filenames
+    char * curr_filename = strrchr(path_to_file, '/') + 1;
+    char * illegal_char = curr_filename;
+    while ((illegal_char = strpbrk(illegal_char, ILLEGAL_CHARS)))
+    {
+        DEBUG("Illegal char found in filename: %c\n", *illegal_char);
+        if (*illegal_char == '.')
+        {
+            // skip initial . (this is allowed)
+            if (illegal_char == curr_filename)
+                continue;
+            // skip extension delimiter
+            if (strpbrk(illegal_char + 1, ".") == NULL)
+            {
+                illegal_char++;
+                continue;
+            }
+        }
+        *illegal_char = '-';
+    }
+
+    // ensure the extension is .zip
+    char * extension = strrchr(path_to_file, '.');
+    if (extension == NULL || strcmp(extension, ".zip"))
+        strcat(path_to_file, ".zip");
+
+    DEBUG("path: %s\n", path_to_file);
+    FS_Path path = fsMakePath(PATH_ASCII, path_to_file);
+
+    // check if file already exists, and if it does, prompt the user
+    // to overwrite or change name (or exit)
+    Result res = FSUSER_CreateFile(ArchiveSD, path, 0, size);
+    if (R_FAILED(res))
+    {
+        if (res == (long)0xC82044BE)
+        {
+            DEBUG("File already exists\n");
+
+            SwkbdState swkbd;
+
+            swkbdInit(&swkbd, SWKBD_TYPE_NORMAL, 3, max_chars / 2);
+            swkbdSetHintText(&swkbd, "Choose a new filename or tap Overwrite");
+            swkbdSetFeatures(&swkbd, SWKBD_PREDICTIVE_INPUT | SWKBD_DARKEN_TOP_SCREEN);
+
+            swkbdSetButton(&swkbd, SWKBD_BUTTON_LEFT, "Cancel", false);
+            swkbdSetButton(&swkbd, SWKBD_BUTTON_MIDDLE, "Overwrite", false);
+            swkbdSetButton(&swkbd, SWKBD_BUTTON_RIGHT, "Rename", true);
+            swkbdSetValidation(&swkbd, SWKBD_NOTEMPTY_NOTBLANK, SWKBD_FILTER_CALLBACK, -1);
+            swkbdSetFilterCallback(&swkbd, &fat32filter, NULL);
+
+            SwkbdButton button = swkbdInputText(&swkbd, new_filename, max_chars);
+
+            switch (button)
+            {
+            case SWKBD_BUTTON_RIGHT:
+                DEBUG("Renaming to %s\n", new_filename);
+                strcat(new_filename, ".zip");
+                filename = new_filename;
+                goto renamed;
+            case SWKBD_BUTTON_MIDDLE:
+                // we good
+                DEBUG("Overwriting %s\n", filename);
+                break;
+            case SWKBD_BUTTON_LEFT:
+                // do nothing
+                DEBUG("File rename cancelled\n");
+                return;
+            case SWKBD_BUTTON_NONE:
+                DEBUG("SWKBD broke wtf??? :- %x\n", swkbdGetResult(&swkbd));
+                return throw_error("???\nTry a USB keyboard", ERROR_LEVEL_WARNING);
+            }
+        }
+        else if (res == (long)0xC86044D2)
+        {
+            DEBUG("SD card is full\n");
+            return throw_error("SD card is full.\nDelete some themes to make space.", ERROR_LEVEL_WARNING);
+        }
+        else
+        {
+            DEBUG("error: %lx\n", res);
+            return throw_error("FS Error:\nGet a new SD card.", ERROR_LEVEL_ERROR);
+        }
+    }
+
+    DEBUG("Saving to SD: %s\n", path_to_file);
+    remake_file(path, ArchiveSD, size);
+    buf_to_file(size, path, ArchiveSD, buf);
+}

source/remote.c

@@ -24,6 +24,8 @@
 *         reasonable ways as different from the original version.
 */
 
+#include <ctype.h>
+
 #include "remote.h"
 #include "loading.h"
 #include "fs.h"
@@ -358,17 +360,8 @@ static void download_remote_entry(Entry_s * entry, EntryMode mode)
     }
     free(download_url);
 
-    char path_to_file[0x107] = { 0 };
+    save_zip_to_sd(filename, zip_size, zip_buf, mode);
-    sprintf(path_to_file, "%s%s", main_paths[mode], filename);
     free(filename);
-
-    char * extension = strrchr(path_to_file, '.');
-    if (extension == NULL || strcmp(extension, ".zip"))
-        strcat(path_to_file, ".zip");
-
-    DEBUG("Saving to SD: %s\n", path_to_file);
-    remake_file(fsMakePath(PATH_ASCII, path_to_file), ArchiveSD, zip_size);
-    buf_to_file(zip_size, fsMakePath(PATH_ASCII, path_to_file), ArchiveSD, zip_buf);
     free(zip_buf);
 }
 
@@ -759,7 +752,6 @@ typedef enum ParseResult
     SUCCESS, // 200/203 (203 indicates a successful request with a transformation applied by a proxy)
     REDIRECT, // 301/302/307/308
     HTTPC_ERROR,
-    ABORTED,
     SERVER_IS_MISBEHAVING,
     SEE_OTHER = 303, // Theme Plaza returns these
     HTTP_UNAUTHORIZED = 401,
@@ -856,7 +848,7 @@ static ParseResult parse_header(struct header * out, httpcContext * context, con
         out->result_code = httpcGetResponseHeader(context, "Content-Disposition", content_buf, 1024);
         if (R_FAILED(out->result_code))
         {
-            if (out->result_code == 0xD8A0A028)
+            if (out->result_code == (long)0xD8A0A028L)
                 present = 0;
             else
             {
@@ -867,55 +859,37 @@ static ParseResult parse_header(struct header * out, httpcContext * context, con
 
         // content_buf: Content-Disposition: attachment; ... filename=<filename>;? ...
 
-        if (!present)
+        if (present)
         {
-            const int max_chars = 250;
+            char * filename = strstr(content_buf, "filename="); // filename=<filename>;? ...
-            // needs to be heap allocated only because the call site is expected to free it
+            // in the extreme fringe case that filename is missing:
-            *out->filename = malloc(max_chars + 5); // + .zip and the null term
+            if (filename != NULL)
-
-            SwkbdState swkbd;
-
-            swkbdInit(&swkbd, SWKBD_TYPE_NORMAL, 2, max_chars / 2);
-            swkbdSetHintText(&swkbd, "Choose a filename");
-            swkbdSetFeatures(&swkbd, SWKBD_PREDICTIVE_INPUT | SWKBD_DARKEN_TOP_SCREEN);
-
-            swkbdSetButton(&swkbd, SWKBD_BUTTON_LEFT, "Cancel", false);
-            swkbdSetButton(&swkbd, SWKBD_BUTTON_RIGHT, "Download", true);
-            swkbdSetValidation(&swkbd, SWKBD_NOTEMPTY_NOTBLANK, SWKBD_FILTER_CALLBACK, -1);
-            swkbdSetFilterCallback(&swkbd, &fat32filter, NULL);
-
-            SwkbdButton button = swkbdInputText(&swkbd, *out->filename, max_chars);
-
-            if (button != SWKBD_BUTTON_CONFIRM)
             {
-                out->result_code = swkbdGetResult(&swkbd);
+                filename = strpbrk(filename, "=") + 1; // <filename>;?
-                return ABORTED;
+                char * end = strpbrk(filename, ";");
+                if (end)
+                    *end = '\0'; // <filename>
+
+                // safe to assume the filename is quoted
+                // (if it isn't, then we already have a null-terminated string <filename>)
+                if (filename[0] == '"')
+                {
+                    filename[strlen(filename) - 1] = '\0';
+                    filename++;
+                }
+
+                *out->filename = malloc(strlen(filename) + 1);
+                strcpy(*out->filename, filename);
+            }
+            else
+            {
+                *out->filename = NULL;
             }
-
-            strcat(*out->filename, ".zip");
-            return SUCCESS;
         }
-
+        else
-        char * filename = strstr(content_buf, "filename="); // filename=<filename>;? ...
-        filename = strpbrk(filename, "=") + 1; // <filename>;?
-        char * end = strpbrk(filename, ";");
-        if (end)
-            *end = '\0'; // <filename>
-
-        if (filename[0] == '"')
-            // safe to assume the filename is quoted
         {
-            filename[strlen(filename) - 1] = '\0';
+            *out->filename = NULL;
-            filename++;
         }
-
-        char * illegal_char;
-        // filter out characters illegal in FAT32 filenames
-        while ((illegal_char = strpbrk(filename, "><\"?;:/\\+,.|[=]")))
-            *illegal_char = '-';
-
-        *out->filename = malloc(strlen(filename) + 1);
-        strcpy(*out->filename, filename);
     }
     return SUCCESS;
 }
@@ -967,11 +941,6 @@ redirect: // goto here if we need to redirect
     {
     case SUCCESS:
         break;
-    case ABORTED:
-        ret = httpcCloseContext(&context);
-        if(R_FAILED(ret))
-            return ret;
-        return MAKERESULT(RL_SUCCESS, RS_CANCELED, RM_APPLICATION, RD_CANCEL_REQUESTED);
     case HTTPC_ERROR:
         DEBUG("httpc error %lx\n", _header.result_code);
         snprintf(err_buf, ERROR_BUFFER_SIZE, "Error in HTTPC sysmodule - 0x%08lx.\nIf you are seeing this, please contact an\nAnemone developer on the Theme Plaza Discord.", _header.result_code);