set up unified lisp library and extensions subsystem.

common/genlib.c

@@ -0,0 +1,219 @@
+/*
+ * genlib.c: generate unified LispLibrary.h for the various uLisp
+ * platforms I work on.
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+
+#define MAX_FILENAME 256
+#define MAX_STRFTIME 32
+#define BUFFER_SIZE 4096
+
+
+const char	lisp_output[] = "LispLibrary.h";
+
+
+/*
+ * Determines whether a directory exists.
+ */
+int
+path_exists(const char *path)
+{
+	struct stat	   st;
+	int		   rv;
+
+	rv = stat(path, &st);
+	if (rv == -1) {
+		return 0;
+	}
+
+	if (st.st_mode & S_IFDIR) {
+		return 1;
+	}
+	else if (st.st_mode & S_IFREG) {
+		return 1;
+	}
+
+	return 1;
+}
+
+
+/*
+ * Unlike some other functions, it is an error to call copy_library if the path
+ * doesn't exist. Other functions (such as copy_platform_library) will validate
+ * the file exists first and skip it if it doesn't.
+ */
+static int
+copy_library(const char *filename, int source_fd)
+{
+
+	char	buffer[BUFFER_SIZE];
+	ssize_t	bytes_read = 0;
+	ssize_t	bytes_written = 0;
+	int	fd = -1;
+
+	fd = open(filename, O_RDONLY);
+	if (fd == -1) {
+		return -1;
+	}
+
+	while ((bytes_read = read(fd, buffer, sizeof(buffer))) > 0) {
+		bytes_written = write(source_fd, buffer, bytes_read);
+		if (bytes_written != bytes_read) {
+			close(fd);
+			return -1;
+		}
+	}
+
+	if (bytes_read == -1) {
+		close(fd);
+		return -1;
+	}
+
+	close(fd);
+	return 0;
+}
+
+
+static int
+copy_platform_library(const char *platform, int dest_fd) {
+	char	filename[MAX_FILENAME];
+
+	if (!platform || !*platform) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	printf("[+] attempting to load %s-specific library...\n",
+	    platform);
+
+	if (snprintf(filename, sizeof(filename), "%s.lsp", platform) >=
+	    (int)sizeof(filename)) {
+		errno = ENAMETOOLONG;
+		return -1;
+	}
+
+	if (!path_exists(filename)) {
+		printf("\t[+] %s-specific library not found; skipping.\n",
+		    platform);
+		return 0;
+	}
+
+	dprintf(dest_fd, "(when (eq (platform) :%s)", platform);
+
+	if (copy_library(filename, dest_fd) != 0) {
+		perror("[!] copying failed");
+		return -1;
+	}
+
+	dprintf(dest_fd, ")\n");
+
+	return 0;
+}
+
+
+static void
+write_preamble(int dest_fd)
+{
+	char		timestamp[MAX_STRFTIME+1];
+	struct tm	tm;
+	time_t		now = time(NULL);
+
+	localtime_r(&now, &tm);
+
+	dprintf(dest_fd,
+	    "/*\n"
+	    " * LispLibrary.h - builtin library of additional uLisp functions\n"
+	    " *\n"
+	    " * NOTE:\n"
+	    " * this file was automatically generated on %s\n"
+	    " *\n"
+	    " * Changes will not be persisted across builds or platforms.\n"
+	    " */\n\n"
+	    "const char LispLibrary[] PROGMEM = R\"lisplibrary(\n\n",
+	    timestamp);
+}
+
+
+static void
+write_epilogue(int dest_fd)
+{
+	dprintf(dest_fd, "\n)lisplibrary\";\n");
+}
+
+
+static void
+usage(int status)
+{
+	FILE	*output = stdout;
+
+	if (status != 0) {
+		output = stderr;
+	}
+
+	fprintf(output, "Usage: genlib [-h]\n"
+	    ""
+	    "Generates a unified LispLibrary.h for the various platforms.\n");
+	exit(status);
+}
+
+
+int
+main(int argc, const char *argv[])
+{
+	int	fd = -1;
+	int	ch;
+
+	while ((ch = getopt(argc, (char **)argv, "h")) != -1) {
+		switch (ch) {
+		case 'h':
+			usage(0);
+			break;
+		default:
+			usage(1);
+		}
+	}
+
+	argc -= optind;
+	argv += optind;
+
+	fd = open(lisp_output, O_WRONLY|O_CREAT, 0644);
+	if (fd == -1) {
+		perror("[!] failed to open library for write");
+		exit(1);
+	}
+
+	write_preamble(fd);
+	if (copy_library("library.lsp", fd) != 0) {
+		fprintf(stderr, "[!] failed to generate %s.\n", lisp_output);
+		exit(1);
+	}
+
+	if (copy_platform_library("picocalc", fd) != 0) {
+		fprintf(stderr, "[!] failed to generate the picocalc component.\n");
+		exit(1);
+	}
+
+	if (copy_platform_library("t-deck", fd) != 0) {
+		fprintf(stderr, "[!] failed to generate the picocalc component.\n");
+		exit(1);
+	}
+
+	if (copy_platform_library("teensy", fd) != 0) {
+		fprintf(stderr, "[!] failed to generate the picocalc component.\n");
+		exit(1);
+	}
+
+	write_epilogue(fd);
+
+	close(fd);
+}