--- /dev/null
+/*-
+ * Copyright 2010-2012 Chris Spiegel.
+ *
+ * This file is part of Bocfel.
+ *
+ * Bocfel is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version
+ * 2 or 3, as published by the Free Software Foundation.
+ *
+ * Bocfel is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Bocfel. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <limits.h>
+
+#ifdef ZTERP_GLK
+#include <glk.h>
+#endif
+
+#include "io.h"
+#include "osdep.h"
+#include "unicode.h"
+
+#define MAX_PATH 4096
+
+int use_utf8_io;
+
+/* Generally speaking, UNICODE_LINEFEED (10) is used as a newline. Glk
+ * requires this (Glk API 0.7.0 §2.2), and when Unicode is available, we
+ * write characters out by hand even with stdio, so no translation can
+ * be done. However, when stdio is being used, Unicode is not
+ * available, and the file usage will be for a transcript or
+ * command-script, use '\n' as a newline so translation can be done;
+ * this is the only case where streams are opened in text mode.
+ *
+ * zterp_io_stdio() and zterp_io_stdout() are considered text-mode if
+ * Unicode is not available, binary otherwise.
+ */
+#define textmode(io) (!use_utf8_io && ((io->mode) & (ZTERP_IO_TRANS | ZTERP_IO_INPUT)))
+
+struct zterp_io
+{
+ enum type { IO_STDIO, IO_GLK } type;
+
+ FILE *fp;
+ int mode;
+#ifdef ZTERP_GLK
+ strid_t file;
+#endif
+};
+
+/* Glk does not like you to be able to pass a full filename to
+ * glk_fileref_create_by_name(); this means that Glk cannot be used to
+ * open arbitrary files. However, Glk is still required to prompt for
+ * files, such as in a save game situation. To allow zterp_io to work
+ * for opening files both with and without a prompt, it will use stdio
+ * when either Glk is not available, or when Glk is available but
+ * prompting is not necessary.
+ *
+ * This is needed because the IFF parser is required for both opening
+ * games (zblorb files) and for saving/restoring. The former needs to
+ * be able to access any file on the filesystem, and the latter needs to
+ * prompt. This is a headache.
+ *
+ * Prompting is assumed to be necessary if “filename” is NULL.
+ */
+zterp_io *zterp_io_open(const char *filename, int mode)
+{
+ zterp_io *io;
+ char smode[] = "wb";
+
+ fprintf(stderr, "zterp_io_open: '%s'\n", filename);
+
+ io = malloc(sizeof *io);
+ if(io == NULL) goto err;
+ io->mode = mode;
+
+ if (mode & ZTERP_IO_RDONLY) smode[0] = 'r';
+ else if(mode & ZTERP_IO_APPEND) smode[0] = 'a';
+
+ if(textmode(io)) smode[1] = 0;
+
+#ifdef ZTERP_GLK
+ int usage = fileusage_BinaryMode, filemode;
+
+ if (mode & ZTERP_IO_SAVE) usage |= fileusage_SavedGame;
+ else if(mode & ZTERP_IO_TRANS) usage |= fileusage_Transcript;
+ else if(mode & ZTERP_IO_INPUT) usage |= fileusage_InputRecord;
+ else usage |= fileusage_Data;
+
+ if (mode & ZTERP_IO_RDONLY) filemode = filemode_Read;
+ else if(mode & ZTERP_IO_WRONLY) filemode = filemode_Write;
+ else if(mode & ZTERP_IO_APPEND) filemode = filemode_WriteAppend;
+
+ else goto err;
+#else
+ const char *prompt;
+
+ if (mode & ZTERP_IO_SAVE) prompt = "Enter filename for save game: ";
+ else if(mode & ZTERP_IO_TRANS) prompt = "Enter filename for transcript: ";
+ else if(mode & ZTERP_IO_INPUT) prompt = "Enter filename for command record: ";
+ else prompt = "Enter filename for data: ";
+#endif
+
+ /* No need to prompt. */
+ if(filename != NULL)
+ {
+ io->type = IO_STDIO;
+ io->fp = fopen(filename, smode);
+ if(io->fp == NULL) goto err;
+ }
+ /* Prompt. */
+ else
+ {
+#ifdef ZTERP_GLK
+ frefid_t ref;
+
+ ref = glk_fileref_create_by_prompt(usage, filemode, 0);
+ if(ref == NULL) goto err;
+
+ io->type = IO_GLK;
+ io->file = glk_stream_open_file(ref, filemode, 0);
+ glk_fileref_destroy(ref);
+ if(io->file == NULL) goto err;
+#else
+ char fn[MAX_PATH], *p;
+
+ printf("\n%s", prompt);
+ fflush(stdout);
+ if(fgets(fn, sizeof fn, stdin) == NULL || fn[0] == '\n') goto err;
+ p = strchr(fn, '\n');
+ if(p != NULL) *p = 0;
+
+ io->type = IO_STDIO;
+ io->fp = fopen(fn, smode);
+ if(io->fp == NULL) goto err;
+#endif
+ }
+
+ return io;
+
+err:
+ free(io);
+
+ return NULL;
+}
+
+/* The zterp_os_reopen_binary() calls attempt to reopen stdin/stdout as
+ * binary streams so that reading/writing UTF-8 doesn’t cause unwanted
+ * translations. The mode of ZTERP_IO_TRANS is set when Unicode is
+ * unavailable as a way to signal that these are text streams.
+ */
+const zterp_io *zterp_io_stdin(void)
+{
+ static zterp_io io;
+
+ if(io.fp == NULL)
+ {
+ io.type = IO_STDIO;
+ io.mode = ZTERP_IO_RDONLY;
+ if(use_utf8_io) zterp_os_reopen_binary(stdin);
+ else io.mode |= ZTERP_IO_TRANS;
+ io.fp = stdin;
+ }
+
+ return &io;
+}
+
+const zterp_io *zterp_io_stdout(void)
+{
+ static zterp_io io;
+
+ if(io.fp == NULL)
+ {
+ io.type = IO_STDIO;
+ io.mode = ZTERP_IO_WRONLY;
+ if(use_utf8_io) zterp_os_reopen_binary(stdout);
+ else io.mode |= ZTERP_IO_TRANS;
+ io.fp = stdout;
+ }
+
+ return &io;
+}
+
+void zterp_io_close(zterp_io *io)
+{
+#ifdef ZTERP_GLK
+ if(io->type == IO_GLK)
+ {
+ glk_stream_close(io->file, NULL);
+ }
+ else
+#endif
+ {
+ fclose(io->fp);
+ }
+
+ free(io);
+}
+
+int zterp_io_seek(const zterp_io *io, long offset, int whence)
+{
+ /* To smooth over differences between Glk and standard I/O, don’t
+ * allow seeking in append-only streams.
+ */
+ if(io->mode & ZTERP_IO_APPEND) return -1;
+
+#ifdef ZTERP_GLK
+ if(io->type == IO_GLK)
+ {
+ glk_stream_set_position(io->file, offset, whence == SEEK_SET ? seekmode_Start : whence == SEEK_CUR ? seekmode_Current : seekmode_End);
+ return 0; /* dammit */
+ }
+ else
+#endif
+ {
+ return fseek(io->fp, offset, whence);
+ }
+}
+
+long zterp_io_tell(const zterp_io *io)
+{
+#ifdef ZTERP_GLK
+ if(io->type == IO_GLK)
+ {
+ return glk_stream_get_position(io->file);
+ }
+ else
+#endif
+ {
+ return ftell(io->fp);
+ }
+}
+
+/* zterp_io_read() and zterp_io_write() always operate in terms of
+ * bytes, whether or not Unicode is available.
+ */
+size_t zterp_io_read(const zterp_io *io, void *buf, size_t n)
+{
+#ifdef ZTERP_GLK
+ if(io->type == IO_GLK)
+ {
+ glui32 s = glk_get_buffer_stream(io->file, buf, n);
+ /* This should only happen if io->file is invalid. */
+ if(s == (glui32)-1) s = 0;
+ return s;
+ }
+ else
+#endif
+ {
+ return fread(buf, 1, n, io->fp);
+ }
+}
+
+size_t zterp_io_write(const zterp_io *io, const void *buf, size_t n)
+{
+#ifdef ZTERP_GLK
+ if(io->type == IO_GLK)
+ {
+ glk_put_buffer_stream(io->file, (char *)buf, n);
+ return n; /* dammit */
+ }
+ else
+#endif
+ {
+ return fwrite(buf, 1, n, io->fp);
+ }
+}
+
+int zterp_io_read16(const zterp_io *io, uint16_t *v)
+{
+ uint8_t buf[2];
+
+ if(zterp_io_read(io, buf, sizeof buf) != sizeof buf) return 0;
+
+ *v = (buf[0] << 8) | buf[1];
+
+ return 1;
+}
+
+int zterp_io_read32(const zterp_io *io, uint32_t *v)
+{
+ uint8_t buf[4];
+
+ if(zterp_io_read(io, buf, sizeof buf) != sizeof buf) return 0;
+
+ *v = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
+
+ return 1;
+}
+
+/* Read a byte and make sure it’s part of a valid UTF-8 sequence. */
+static int read_byte(const zterp_io *io, uint8_t *c)
+{
+ if(zterp_io_read(io, c, sizeof *c) != sizeof *c) return 0;
+ if((*c & 0x80) != 0x80) return 0;
+
+ return 1;
+}
+
+/* zterp_io_getc() and zterp_io_putc() are meant to operate in terms of
+ * characters, not bytes. That is, unlike C, bytes and characters are
+ * not equivalent as far as Zterp’s I/O system is concerned.
+ */
+
+/* Read a UTF-8 character, returning it.
+ * -1 is returned on EOF.
+ *
+ * If there is a problem reading the UTF-8 (either from an invalid
+ * sequence or from a too-large value), a question mark is returned.
+ *
+ * If Unicode is not available, read a single byte (assumed to be
+ * Latin-1).
+ * If Unicode is not available, IO_STDIO is in use, and text mode is
+ * set, do newline translation. Text mode is likely to always be
+ * set—this function really shouldn’t be used in binary mode.
+ */
+long zterp_io_getc(const zterp_io *io)
+{
+ long ret;
+
+ if(!use_utf8_io)
+ {
+#ifdef ZTERP_GLK
+ if(io->type == IO_GLK)
+ {
+ ret = glk_get_char_stream(io->file);
+ }
+ else
+#endif
+ {
+ int c;
+
+ c = getc(io->fp);
+ if(c == EOF) ret = -1;
+ else ret = c;
+
+ if(textmode(io) && c == '\n') ret = UNICODE_LINEFEED;
+ }
+ }
+ else
+ {
+ uint8_t c;
+
+ if(zterp_io_read(io, &c, sizeof c) != sizeof c)
+ {
+ ret = -1;
+ }
+ else if((c & 0x80) == 0) /* One byte. */
+ {
+ ret = c;
+ }
+ else if((c & 0xe0) == 0xc0) /* Two bytes. */
+ {
+ ret = (c & 0x1f) << 6;
+
+ if(!read_byte(io, &c)) return UNICODE_QUESTIONMARK;
+
+ ret |= (c & 0x3f);
+ }
+ else if((c & 0xf0) == 0xe0) /* Three bytes. */
+ {
+ ret = (c & 0x0f) << 12;
+
+ if(!read_byte(io, &c)) return UNICODE_QUESTIONMARK;
+
+ ret |= ((c & 0x3f) << 6);
+
+ if(!read_byte(io, &c)) return UNICODE_QUESTIONMARK;
+
+ ret |= (c & 0x3f);
+ }
+ else if((c & 0xf8) == 0xf0) /* Four bytes. */
+ {
+ /* The Z-machine doesn’t support Unicode this large, but at
+ * least try not to leave a partial character in the stream.
+ */
+ zterp_io_seek(io, 3, SEEK_CUR);
+
+ ret = UNICODE_QUESTIONMARK;
+ }
+ else /* Invalid value. */
+ {
+ ret = UNICODE_QUESTIONMARK;
+ }
+ }
+
+ if(ret > UINT16_MAX) ret = UNICODE_QUESTIONMARK;
+
+ return ret;
+}
+
+/* Write a Unicode character as UTF-8.
+ *
+ * If Unicode is not available, write the value out as a single Latin-1
+ * byte. If it is too large for a byte, write out a question mark.
+ *
+ * If Unicode is not available, IO_STDIO is in use, and text mode is
+ * set, do newline translation.
+ *
+ * Text mode is likely to always be set—this function really shouldn’t
+ * be used in binary mode.
+ */
+void zterp_io_putc(const zterp_io *io, uint16_t c)
+{
+ if(!use_utf8_io)
+ {
+ if(c > UINT8_MAX) c = UNICODE_QUESTIONMARK;
+#ifdef ZTERP_GLK
+ if(io->type == IO_GLK)
+ {
+ glk_put_char_stream(io->file, c);
+ }
+ else
+#endif
+ {
+ if(textmode(io) && c == UNICODE_LINEFEED) c = '\n';
+ putc(c, io->fp);
+ }
+ }
+ else
+ {
+ uint8_t hi = c >> 8, lo = c & 0xff;
+
+#define WRITE(c) zterp_io_write(io, &(uint8_t){ c }, sizeof (uint8_t))
+ if(c < 128)
+ {
+ WRITE(c);
+ }
+ else if(c < 2048)
+ {
+ WRITE(0xc0 | (hi << 2) | (lo >> 6));
+ WRITE(0x80 | (lo & 0x3f));
+ }
+ else
+ {
+ WRITE(0xe0 | (hi >> 4));
+ WRITE(0x80 | ((hi << 2) & 0x3f) | (lo >> 6));
+ WRITE(0x80 | (lo & 0x3f));
+ }
+#undef WRITE
+ }
+}
+
+long zterp_io_readline(const zterp_io *io, uint16_t *buf, size_t len)
+{
+ long ret;
+
+ if(len > LONG_MAX) return -1;
+
+ for(ret = 0; ret < len; ret++)
+ {
+ long c = zterp_io_getc(io);
+
+ /* EOF before newline means there was a problem. */
+ if(c == -1) return -1;
+
+ /* Don’t count the newline. */
+ if(c == UNICODE_LINEFEED) break;
+
+ buf[ret] = c;
+ }
+
+ return ret;
+}
+
+long zterp_io_filesize(const zterp_io *io)
+{
+ if(io->type == IO_STDIO && !textmode(io))
+ {
+ return zterp_os_filesize(io->fp);
+ }
+ else
+ {
+ return -1;
+ }
+}
+
+void zterp_io_flush(const zterp_io *io)
+{
+ if(io == NULL || io->type != IO_STDIO || !(io->mode & (ZTERP_IO_WRONLY | ZTERP_IO_APPEND))) return;
+
+ fflush(io->fp);
+}