bb

text_rendering/util.c

@@ -0,0 +1,98 @@
+#define _POSIX_C_SOURCE 200809l
+
+#include <sys/mman.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <err.h>
+
+#include "util.h"
+
+
+const char *bit_rep[16] = {
+    [ 0] = "0000", [ 1] = "0001", [ 2] = "0010", [ 3] = "0011",
+    [ 4] = "0100", [ 5] = "0101", [ 6] = "0110", [ 7] = "0111",
+    [ 8] = "1000", [ 9] = "1001", [10] = "1010", [11] = "1011",
+    [12] = "1100", [13] = "1101", [14] = "1110", [15] = "1111",
+};
+
+
+
+void * emalloc(unsigned long int size)
+{
+	void *r = malloc(size);
+	if (!r)
+		err(EXIT_FAILURE, "malloc() of size %ld", size);
+	return r;
+}
+
+
+void * ecalloc(unsigned long int nmemb, unsigned long int size)
+{
+	void *r = calloc(nmemb, size);
+	if (!r)
+		err(EXIT_FAILURE, "calloc() of size %ld, nmemb %ld", size, nmemb);
+	return r;
+}
+
+
+void efree(void *ptr)
+{
+	if (ptr)
+		free(ptr);
+}
+
+
+void map_file(const unsigned char **str, int *size, const char *path)
+{
+	if (!path) {
+		errno = EINVAL;
+		err(EXIT_FAILURE, "NULL filename");
+	}
+	FILE *fp = fopen(path, "r");
+	if (!fp)
+		err(EXIT_FAILURE, "Cannot open file %s", path);
+	*size = lseek(fileno(fp), 0, SEEK_END);
+	if (*size == (off_t)-1)
+		err(EXIT_FAILURE, "lseek() failed");
+	*str = mmap(0, *size, PROT_READ, MAP_PRIVATE, fileno(fp), 0);
+	if (*str == (void*)-1)
+		err(EXIT_FAILURE, "mmap() failed");
+	if (fclose(fp))
+		err(EXIT_FAILURE, "Error closing file");
+}
+
+
+void dump_file(const char *path, unsigned char **buf, int *buf_len)
+{
+	if (!path) {
+		errno = EINVAL;
+		err(EXIT_FAILURE, "NULL filename");
+	}
+	if (!buf) {
+		errno = EINVAL;
+		err(EXIT_FAILURE, "No buffer specified");
+	}
+	if (!buf_len) {
+		errno = EINVAL;
+		err(EXIT_FAILURE, "Nowhere to store buffer size");
+	}
+	FILE *fp = fopen(path, "r");
+	if (!fp)
+		err(EXIT_FAILURE, "Cannot open file %s", path);
+	*buf_len = lseek(fileno(fp), 0, SEEK_END);
+	if (*buf_len == (off_t)-1)
+		err(EXIT_FAILURE, "lseek() failed");
+	*buf = emalloc(*buf_len);
+	*buf_len = fread(*buf, 1, *buf_len, fp);
+	if (fclose(fp))
+		err(EXIT_FAILURE, "Error closing file");
+}
+
+
+void print_byte(unsigned char byte)
+{
+	printf("%s%s", bit_rep[byte >> 4], bit_rep[byte & 0x0F]);
+}