X-Git-Url: https://git.distorted.org.uk/~mdw/dvdrip/blobdiff_plain/972381afacd6efbd0d20c77ff7e00981f95b7418..refs/heads/mdw/cleanup:/lib.h
diff --git a/lib.h b/lib.h
index 069cd37..7c4a0cb 100644
--- a/lib.h
+++ b/lib.h
@@ -1,9 +1,38 @@
+/* -*-c-*-
+ *
+ * Common functions for the DVDrip C utilities.
+ *
+ * (c) 2022 Mark Wooding
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of the DVD ripping toolset.
+ *
+ * DVDrip is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * DVDrip 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 DVDrip. If not, see .
+ */
+
#ifndef LIB_H
#define LIB_H
+/*----- Preliminaries -----------------------------------------------------*/
+
#define _GNU_SOURCE
#define _FILE_OFFSET_BITS 64
+/*----- Header files ------------------------------------------------------*/
+
#include
#include
#include
@@ -37,85 +66,326 @@
#include "multiprogress.h"
+/*----- Various macros with wide applicability ----------------------------*/
+
+/* `ctype.h' functions are troublesome: in particular, they don't handle
+ * negative characters properly, if they're a thing that your platform
+ * believes in. So we have these macros which fix things up properly.
+ */
#define CTYPE_HACK(fn, ch) fn((unsigned char)(ch))
#define ISDIGIT(ch) CTYPE_HACK(isdigit, ch)
#define ISSPACE(ch) CTYPE_HACK(isspace, ch)
+/* It's easy to screw up the `foocmp' functions by leaving off the comparison
+ * with zero. These macros make it impossible to forget, and put the
+ * relation in the right place syntactically.
+ */
#define STRCMP(a, op, b) (strcmp((a), (b)) op 0)
#define STRNCMP(a, op, b, n) (strncmp((a), (b), (n)) op 0)
#define MEMCMP(a, op, b, n) (memcmp((a), (b), (n)) op 0)
+/* Suppress some code unless we're debugging. */
#ifdef DEBUG
# define D(x) x
#else
# define D(x)
#endif
+/* Count the number of elements in an array. */
#define N(v) (sizeof(v)/sizeof((v)[0]))
-#define SECTORSZ 2048
+/* Function attributes. If you're not using GCC to build then you'll need to
+ * say something different here.
+ */
+#if (defined(__GNUC__) && (__GNUC__ > 2 || \
+ (__GNUC__ == 2 && __GNUC_MINOR__ >= 5))) || \
+ (defined(__clang__) && (__clang_major__ > 3 || \
+ (__clang_major__ == 3 && __clang_minor__ >= 3)))
+# define PRINTF_LIKE(fmt, dots) __attribute__((format(printf, fmt, dots)))
+# define NORETURN __attribute__((noreturn))
+#else
+# define PRINTF_LIKE(fmt, dots)
+# define NORETURN
+#endif
+
+/*----- Definitions for low-level DVD access ------------------------------*/
+
+#define SECTORSZ 2048 /* the DVD sector size */
#define SECTORS(n) (((n) + (SECTORSZ - 1))/SECTORSZ)
-typedef uint_least32_t secaddr;
-#define PRIuSEC PRIuLEAST32
-#define SECLIMIT 0x00400000
+ /* convert bytes to * sectors, rounding up */
+typedef uint_least32_t secaddr; /* a type for sector numbers */
+#define PRIuSEC PRIuLEAST32 /* how to print a sector number */
+#define SECLIMIT 0x00400000 /* upper bound on sector numbers */
-#define PRINTF_LIKE(fmt, dots) __attribute__((format(printf, fmt, dots)))
-#define NORETURN __attribute__((noreturn))
+/*----- Diagnostics -------------------------------------------------------*/
-extern const char *prog;
+extern const char *prog; /* the program name; set with `set_prog' */
extern void set_prog(const char *p);
+ /* Set the program name to P, stripping any directory names. */
+
extern void vmoan(const char *fmt, va_list ap);
extern void vmoan_syserr(int err, const char *fmt, va_list ap);
+ /* Low-level warning reporting. See `moan' and `moan_syserr'. */
+
extern PRINTF_LIKE(1, 2) void moan(const char *fmt, ...);
extern PRINTF_LIKE(2, 3) void moan_syserr(int err, const char *fmt, ...);
+ /* Print a warning message, given as a `printf'-like format string
+ * FMT and arguments, to standard error. If ERR is nonzero, then
+ * append a colon and the human-readable description of the `errno'
+ * value ERR.
+ */
+
extern PRINTF_LIKE(1, 2) NORETURN void bail(const char *fmt, ...);
extern PRINTF_LIKE(2, 3) NORETURN
void bail_syserr(int err, const char *fmt, ...);
+ /* Like the corresponding `moan' functions, except that they also
+ * exit with status code 2.
+ */
+
+/*----- Resizing buffers --------------------------------------------------*/
+
+struct buf {
+ /* A buffer for a string which can grow automatically. */
+
+ char *p; /* pointer to the buffer */
+ size_t n, sz; /* string length, buffer size */
+};
+#define BUF_INIT { 0, 0, 0 }
+
+static inline void buf_rewind(struct buf *b) { b->n = 0; }
+ /* Throw away the current contents of B so that new stuff gets added
+ * to the beginning.
+ */
+
+static inline void buf_free(struct buf *b)
+ { free(b->p); b->p = 0; b->n = b->sz = 0; }
+ /* Release the memory allocated for B. The buffer can be reused
+ * immediately and/or freed again safely.
+ */
+
+extern void buf__grow(struct buf *b);
+ /* Make B's buffer larger, so that (at least) one extra byte can be
+ * written to it. (Internal to `buf_putc'.)
+ */
+
+static inline void buf_putc(struct buf *b, int ch)
+ { if (b->n >= b->sz) buf__grow(b); b->p[b->n++] = ch; }
+ /* Append the character CH to the buffer B. */
+
+static inline void buf_putz(struct buf *b)
+ { if (b->n >= b->sz) buf__grow(b); b->p[b->n] = 0; }
+ /* Append a zero byte to B without increasing the string length, so
+ * that a future `buf_putc' will overwrite it.
+ */
+
+/*----- Resizing vectors --------------------------------------------------*/
+
+#define DEFVEC(vtype, etype) \
+ typedef struct { etype *v; size_t n, sz; } vtype
+#define VEC_INIT { 0, 0, 0 }
+ /* Define VTYPE as a (structured) type for vectors holding elements
+ * of ETYPE.
+ *
+ * A vector V has `V.n' elements, addressed as `V.v[0]' up to
+ * `V.v[V.n - 1]'.
+ */
+
+#define VEC_FREE(vv) do { \
+ free((vv)->v); (vv)->v 0; (vv)->n = (vv)->sz = 0; \
+} while (0)
+ /* Free the vector VV. It's safe to free a vector multiple times. */
+
+extern void *vec__grow(void *p, size_t esz, size_t *sz_inout);
+ /* Extend the buffer P, which currently has space for *SZ_INOUT
+ * elements, each ESZ bytes in size, so that there's space for at
+ * least one one more; return the new buffer address, and update
+ * *SZ_INOUT with the new size.
+ */
+
+#define VEC_PUSH(p, vv) do { \
+ if ((vv)->n >= (vv)->sz) \
+ (vv)->v = vec__grow((vv)->v, sizeof(*(vv)->v), &(vv)->sz); \
+ (p) = &(vv)->v[(vv)->n++]; \
+} while (0)
+ /* Add an initialized element to the end of vector VV, storing its
+ * address in P.
+ */
+
+/*----- Parsing utilities -------------------------------------------------*/
#define PNF_JUNK 1u
extern double parse_float(const char **p_inout, unsigned f,
double min, double max, const char *what);
extern long parse_int(const char **p_inout, unsigned f,
long min, long max, const char *what);
+ /* Parse a number starting at *P_IN OUT, advancing that pointer past
+ * it, and return the resulting value. If no number can be read from
+ * the string, or the resulting number is not between MIN and MAX
+ * inclusive, or the `PNF_JUNK' bit is clear in F and the number is
+ * followed by anything other than whitespace, then report a fatal
+ * error, quoting WHAT as having been expected.
+ */
+
+/*----- System utilities --------------------------------------------------*/
+
+extern double tvdiff(const struct timeval *tv_lo,
+ const struct timeval *tv_hi);
+ /* Return the (signed) difference from TV_LO to TV_HI, as a floating-
+ * point number of seconds.
+ */
extern void sit(double t);
+ /* Do nothing for T seconds. As implied by the type, T may be
+ * fractional.
+ */
+
+extern int read_line(FILE *fp, struct buf *b);
+ /* Read a line from FP, appending it to the buffer B, leaving the
+ * string in B null-terminated (as if by `buf_putz'). Return 0 on
+ * success, or -1 if nothing was read (not even an empty line) before
+ * we encountered end-of-file or a read error.
+ */
extern void carefully_write(int fd, const void *buf, size_t sz);
+ /* Write SZ bytes to file descriptor FD, starting at BUF. Report a
+ * fatal error if this fails. Correctly handles short writes and
+ * `EINTR'.
+ */
+
extern void open_file_on_demand(const char *file, FILE **fp_inout,
const char *what);
+ /* If *FP_INOUT is not null, then do nothing. Otherwise, open FILE
+ * for writing, storing the resulting stream handle in *FP_INOUT; if
+ * this can't be done then report a fatal error, quoting WHAT as the
+ * kind of file.
+ */
+
extern void check_write(FILE *fp, const char *what);
+ /* Flush any remaining output to FP and check that there were no
+ * errors. If there were problems, report a fatal error quoting WHAT
+ * as the kind of file.
+ */
+
extern void carefully_fclose(FILE *fp, const char *what);
+ /* Flush output to FP and close it, reporting fatal errors as for
+ * `check_write'. If FP is null, then do nothing.
+ */
+
extern off_t device_size(int fd, const char *file, int *blksz_out);
+ /* Determine the size of the device referred to by FD. Specifically,
+ * if FD is a regular file, then this is simply the size of the file;
+ * if FD is a block device, then this is the size of the block
+ * device. Return the resulting size, and, in the case of a block
+ * device only, store the block size in *BLKSZ_OUT. (Hence,
+ * *BLKSZ_OUT will be left unchanged if FD is open on a regular
+ * file.) If FD refers to any other kind of object then report a
+ * fatal error quoting FILE as the name of the device.
+ */
+
+/*----- Progress utilities ------------------------------------------------*/
+
+struct banner_progress_item {
+ /* A progress item which simply shows a banner message. */
+ struct progress_item _base;
+ const char *msg;
+};
+
+extern struct progress_state progress; /* the shared progress reporter */
+
+extern void show_banner(const char *msg);
+extern void hide_banner(void);
+ /* Show or hide a banner reporting a message. If a banner is already
+ * showing, then `show_banner' just changes the message.
+ */
+
+/*----- DVD utilities -----------------------------------------------------*/
+
+extern int open_dvd(const char *device, int mode,
+ int *fd_out, dvd_reader_t **dvd_out);
+ /* Open the DEVICE. If FD_OUT is not null, then open a file
+ * descriptor onto the device, with the given open(2)-style MODE,
+ * storing the descriptor in *FD_OUT; if DVD_OUT is not null, then
+ * open a `libdvdread' handle onto the devie and store it in
+ * *DVD_OUT. If both are null, then why are you calling this
+ * function? Returns 0 on success or -1 on failure.
+ *
+ * If DEVICE refers to an actual block device, and no medium is
+ * currently inserted, then put up a banner prompting the user and
+ * wait for a medium to be inserted. Other problems are reported to
+ * stderr.
+ */
enum { RAW, IFO, VOB, BUP };
typedef uint_least32_t ident;
+ /* A convenient name for interesting files on a DVD. It consists of
+ * three components:
+ *
+ * * A `kind', which is `RAW', `IFO', `VOB', or `BUP'. `RAW' is a
+ * special token which refers to the whole disc; the other kinds
+ * refer to files in the DVD filesystem with the corresponding
+ * extensions.
+ *
+ * * A `title', which is a number between 0 and 99 inclusive.
+ * Title zero refers to the video management information and its
+ * corresponding menu; nonzero numbers refer to video titlesets.
+ *
+ * * A `part', which is only relevant for `VOB' files; part 0
+ * refers to the menu data, while parts 1 to 9 inclusive refer to
+ * portions of the video titleset itself.
+ *
+ * Components which aren't applicable must be zero, so that idents
+ * can conveniently be compared as integers (so, specifically, the
+ * title, if kind is `RAW', and the part, if kind is not `VOB' or
+ * title is zero.
+ */
static inline ident mkident(unsigned kind, unsigned title, unsigned part)
{ return (((ident)kind << 0) | ((ident)title << 8) | ((ident)part << 16)); }
static inline unsigned id_kind(ident id) { return ((id >> 0)&0x0ff); }
static inline unsigned id_title(ident id) { return ((id >> 8)&0x0ff); }
static inline unsigned id_part(ident id) { return ((id >> 16)&0x0ff); }
+ /* Functions for constructing and picking apart the fields of an
+ * ident.
+ */
#define MAXFNSZ (1 + 8 + 1 + 12 + 1)
extern void store_filename(char *buf, ident id);
+ /* Store in BUF the filename corresponding to the ident ID. The
+ * filename will be at most `MAXFNSZ' bytes long, including the
+ * terminating zero.
+ */
#define DIF_MUSTVOLINF 1u
#define DIF_MUSTIFOHASH 2u
-#define MAXIDSZ 99
+#define MAXIDSZ (32 + 1 + 32 + 1 + 32 + 1)
extern int dvd_id(char *p, dvd_reader_t *dvd, unsigned f, const char *file);
+ /* Determine a (hopefully) unique identifier for DVD. The identifier
+ * consists of two parts:
+ *
+ * * the volume name and serial number, from the volume
+ * information, and
+ *
+ * * a cryptographic hash of the `.IFO' files on the disc.
+ *
+ * The identifier is written, as plain text, at P, and consists of at
+ * most `MAXIDSZ' bytes, including the terminating zero.
+ *
+ * It's possible that determining either, or both, of these might
+ * fail: the behaviour is controlled by the `DIF_MUSTVOLINF' and
+ * `DIF_MUSTIFOHASH' flags in F: if the volume name/serial number, or
+ * `.IFO' hash, respectively, can't be determined, and the
+ * corresponding flag is clear, then a placeholder error message is
+ * written to the output buffer in place of the correct data; if the
+ * flag is set, then a warning message is printed to standard error
+ * and -1 is returned. In practice, the `.IFO' hash is more likely
+ * to be computed successfully, and probably more likely to actually
+ * be unique.
+ *
+ * Returns zero if the identifier was successfully determined, within
+ * the parameters set by the flags.
+ */
-struct banner_progress_item {
- struct progress_item _base;
- const char *msg;
-};
-
-extern struct progress_state progress;
-
-extern void show_banner(const char *msg);
-extern void hide_banner(void);
-
-extern void open_dvd(const char *device, int mode,
- int *fd_out, dvd_reader_t **dvd_out);
+/*----- That's all, folks -------------------------------------------------*/
#endif