driver-install: implemented a simple installer

userspace/programs/driver-install/main.cpp

@@ -0,0 +1,93 @@
+#include <stdio.h>
+#include <assert.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+
+
+char* g_exe;
+char* shift_args(int *argc, char ***argv) {
+	return (assert((*argc) > 0), ((*argc)--, *((*argv)++)));
+}
+void help(FILE* sink) {
+	fprintf(sink, "%s <input filename>\n", g_exe);
+}
+#define eprintf(...) fprintf(stderr, __VA_ARGS__)
+#define eprintfln(fmt, ...) eprintf(fmt "\n", ## __VA_ARGS__)
+char* read_entire_file(const char* path) {
+	char* result = NULL;
+	char* head = NULL;
+	char* end = NULL;
+	size_t buf_size = 0;
+	long at = 0;
+	FILE *f = fopen(path, "rb");
+
+	if(!f) {
+		fprintf(stderr, "ERROR Could not open file %s: %s\n",path,strerror(errno));
+		return NULL;
+	}
+	if(fseek(f, 0, SEEK_END) != 0) {
+		fprintf(stderr, "ERROR Could not fseek on file %s: %s\n",path,strerror(errno));
+		result = NULL; goto DEFER;
+	}
+	at = ftell(f);
+	if(at == -1L) {
+		fprintf(stderr, "ERROR Could not ftell on file %s: %s\n",path,strerror(errno));
+		result = NULL; goto DEFER;
+	}
+	buf_size = at+1;
+	rewind(f);
+	result = (char*)malloc(buf_size);
+	assert(result && "Ran out of memory");
+	head = result;
+	end = result+buf_size-1;
+	while(head != end) {
+		head += fread(head, 1, end-head, f);
+		if(ferror(f)) {
+			fprintf(stderr, "ERROR Could not fread on file %s: %s\n",path,strerror(errno));
+			free(result);
+			result = NULL; goto DEFER;
+		}
+	}
+	result[buf_size-1] = '\0';
+DEFER:
+	fclose(f);
+	return result;
+}
+
+static int banos_install(const void* driver_image) {
+	return syscall(SYS_BANOS_INSTALL, driver_image);
+}
+
+
+int main(int argc, char** argv)
+{
+	g_exe = shift_args(&argc, &argv);
+	char* input_filename = NULL;
+	while(argc > 0) {
+		char* arg = shift_args(&argc, &argv);
+		if(!input_filename) input_filename = arg;
+		else {
+			eprintfln("ERROR: Unexpected argument `%s'", arg);
+			help(stderr);
+			return 1;
+		}
+	}
+	if(!input_filename) {
+		eprintfln("ERROR: Missing input filename!");
+		help(stderr);
+		return 1;
+	}
+	char* data = read_entire_file(input_filename);
+	if(!data) return 1;
+	int id = banos_install(data);
+	if(id == -1) {
+		eprintfln("ERROR: Failed to install driver `%s': %s", input_filename, strerror(errno));
+		return 1;
+	}
+	printf("%d\n", id);
+	return 0;
+}