a quick C cat

lkmc/file_io.h

@@ -0,0 +1,66 @@
+#ifndef LKMC_FILE_IO_H
+#define LKMC_FILE_IO_H
+
+/* Returns the size of the given open `FILE*`.
+ *
+ * If an error occurs, returns `-1L`.
+ *
+ * Does not work for pipes.
+ */
+long lkmc_fget_file_size(FILE *fp) {
+    long oldpos;
+    long return_value;
+    oldpos = ftell(fp);
+    if (oldpos == -1L) {
+        return -1L;
+    }
+    if (fseek(fp, 0, SEEK_END) != 0) {
+        return -1L;
+    }
+    return_value = ftell(fp);
+    if (return_value == -1L) {
+        return -1L;
+    }
+    /* Restore the old position. */
+    if (fseek(fp, oldpos , SEEK_SET) != 0) {
+        return -1L;
+    }
+    return return_value;
+}
+
+/* Read the entire file to a char[] dynamically allocated inside this function.
+ *
+ * Returns a pointer to the start of that array.
+ *
+ * In case of any error, returns NULL.
+ *
+ * http://stackoverflow.com/questions/174531/easiest-way-to-get-files-contents-in-c
+ */
+char *lkmc_file_read(char *path) {
+    FILE *fp;
+    char *buffer;
+    long fsize;
+
+    fp = fopen(path , "rb");
+    if (fp == NULL) {
+        return NULL;
+    }
+    fsize = lkmc_fget_file_size(fp);
+    if (fsize < 0){
+        fprintf(stderr, "could not determine lenght of:\n%s\n", path);
+        return NULL;
+    }
+    buffer = (char*)malloc(fsize);
+    if (buffer == NULL) {
+        return NULL;
+    }
+    if (fread(buffer, 1, fsize, fp) != (size_t)fsize) {
+        return NULL;
+    }
+    if (fclose(fp) == EOF){
+        return NULL;
+    }
+    return buffer;
+}
+
+#endif