Finished with Diskwrite tool, will expand as needed

tools/diskwrite.c

@@ -120,7 +120,9 @@ void write_cluster_value(fat_info *info, uint32_t value, uint32_t cluster){
     }
 }
 
-int write_file(char *path, fat_info *info, FILE *file){
+int read_file(fat_info *info, uint32_t first_cluster, file_t *file, buffer_t *buffer, FILE *disk);
+
+int create_file(char *path, fat_info *info, FILE *file){
     FILE *ifile = fopen(path, "r");
     if(!ifile){
         printf("Failed to open file: %s\nAborting...\n", path);
@@ -140,13 +142,14 @@ int write_file(char *path, fat_info *info, FILE *file){
     }
     //create file in root dir
     file_t dirent = {0};
-    memcpy(dirent.filename, path, 8);
     int extoffset = 0;
     while(*(path + extoffset) != '.' && *(path + extoffset)){
         extoffset++;
     }
+    memcpy(dirent.filename, path, 8 > extoffset ? extoffset : 8);
     verbose && printf("File extension at %d\n", extoffset);
-    memcpy(dirent.ext, path + extoffset, 3);
+    verbose && printf("file ext: %s\n", path + extoffset);
+    memmove(dirent.ext, path + extoffset + 1, 3);
     dirent.size_bytes = ifsize;
     verbose && printf("Writing %u sectors\n", ifsize/(info->bpb.bytes_per_sector * info->bpb.sectors_per_cluster) + 1);
     uint32_t last_cluster = 0;
@@ -164,12 +167,48 @@ int write_file(char *path, fat_info *info, FILE *file){
     verbose && printf("last cluster: %d\n", last_cluster);
     write_cluster_value(info, FILE_END, last_cluster);
     
+    buffer_t root_dir_buffer = 0;
+    uint32_t dirent_count = read_file(info, info->bpb.root_dir_cluster, 0, &root_dir_buffer, file)/sizeof(file_t);
+    
+    //searching for a free dirent
+    file_t *root_dir = (file_t *)root_dir_buffer;
+    uint32_t free_file_index = 0;
+    while(root_dir[free_file_index].filename[0] && free_file_index < dirent_count){
+        free_file_index++;
+    }
+    if(free_file_index >= dirent_count){
+        //!FIXME
+        verbose && printf("could not find free dirent; this will be fixed in a later version\n");
+        exit(-1);
+    }
+    root_dir[free_file_index] = dirent;
+    verbose && printf("Found a free dirent at index %u\n", free_file_index);
+    for(uint32_t i = 0; i < (dirent_count * sizeof(file_t)) / info->bpb.bytes_per_sector /info->bpb.sectors_per_cluster; i++){
+        write_sector(file, (info->bpb.reserved_sectors + (info->bpb.fat_count * info->bpb.sectors_per_fat) + info->file_table[i] * info->bpb.sectors_per_cluster), info->bpb.sectors_per_cluster, (buffer_t)(root_dir + i * info->bpb.sectors_per_cluster * info->bpb.bytes_per_sector));
+        
+    }
 }
 
-int read_file(fat_info *info, uint32_t first_cluster, file_t *file, buffer_t buffer){
+int read_file(fat_info *info, uint32_t first_cluster, file_t *file, buffer_t *buffer, FILE *disk){
+    uint32_t cluster_size_bytes = info->bpb.bytes_per_sector * info->bpb.sectors_per_cluster;
     if(file == 0){
-        buffer_t buf;
+        verbose && printf("Reading starting from cluster %d\n", first_cluster);
-        
+        buffer_t buf = malloc(1);
+        uint32_t allocated = 0;
+        uint32_t cluster = first_cluster;
+        do {
+            allocated++;
+            buf = realloc(buf, cluster_size_bytes * allocated);
+            verbose && printf("Reallocated to %u, ptr: %p\n", allocated * cluster_size_bytes, buf);
+            read_sector(disk, info->bpb.reserved_sectors + (info->bpb.fat_count * info->bpb.sectors_per_fat) + cluster * info->bpb.sectors_per_cluster, info->bpb.sectors_per_cluster, buf + (allocated * cluster_size_bytes));
+            cluster = info->file_table[cluster];
+        }while(cluster != FILE_END);
+        if(*buffer != 0){
+            free(buffer);
+        }
+        verbose && printf("Read %d cluster starting from cluster %d\n", allocated, first_cluster);
+        *buffer = buf;
+        return allocated * cluster_size_bytes;
     }
 }
 
@@ -238,7 +277,7 @@ int main(int argc, char **argv){
     detect_repair_fs(output_file, &info);
     verbose && printf("Finished. Exiting...\n");
     for(int i = 0; i < filec; i++){
-        write_file(files[i], &info, output_file);
+        create_file(files[i], &info, output_file);
     }
     fat_write_back(output_file, &info);
     return 0;