1 files changed, 55 insertions, 0 deletions
diff --git a/src/fileutils.c b/src/fileutils.c
index ea57550..fe9ab88 100644
--- a/src/fileutils.c
+++ b/src/fileutils.c
@@ -5,6 +5,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
+#include <limits.h>
 #include <pwd.h>
 #include <unistd.h>
 #include <fcntl.h>
@@ -80,3 +81,57 @@ int create_directory_recursive(char *path) {
     }
     return 0;
 }
+
+int file_exists(const char *path) {
+    struct stat st;
+    return stat(path, &st);
+}
+
+int create_lock_file(const char *path) {
+    int fd = open(path, O_CREAT | O_EXCL);
+    if(fd == -1)
+        return errno;
+    fsync(fd);
+    return close(fd);
+}
+
+int file_overwrite(const char *filepath, const char *data, size_t size) {
+    FILE *file = fopen(filepath, "wb");
+    if(!file) {
+        int err = -errno;
+        perror(filepath);
+        return err;
+    }
+
+    unsigned long bytes_written = fwrite(data, 1, size, file);
+    if(bytes_written != size) {
+        fprintf(stderr, "Failed to write all bytes to file %s. Expected to write %zu bytes, only wrote %zu bytes\n", filepath, size, bytes_written);
+        fclose(file);
+        return -1;
+    }
+
+    fclose(file);
+    return 0;
+}
+
+int file_overwrite_in_dir(const char *dir, const char *filename, const char *data, size_t size) {
+    char filepath[PATH_MAX];
+    const char *filepath_components[] = { dir, filename };
+    path_join(filepath, filepath_components, 2);
+    return file_overwrite(filepath, data, size);
+}
+
+void path_join(char *output, const char **components, int num_components) {
+    int offset = 0;
+    for(int i = 0; i < num_components; ++i) {
+        if(i > 0) {
+            output[offset] = '/';
+            ++offset;
+        }
+
+        int component_len = strlen(components[i]);
+        memcpy(output + offset, components[i], component_len);
+        offset += component_len;
+    }
+    output[offset] = '\0';
+}