#define _LARGEFILE_SOURCE #define _FILE_OFFSET_BITS 64 #include #include #include #include #include #include /** Echo digital video frames to stdout * @param smil SMIL file name (for diagnostics) * @param lineno SMIL file line number * @param dvname digital video file name * @param begin first frame to display * @param end last frame to display * @return zero on success, nonzero on error */ static int dvread (const char* smil, unsigned lineno, const char* dvname, unsigned begin, unsigned end) { FILE* f; static char frame[144000]; unsigned framelen = 144000; /** current frame */ unsigned curr = 0; if (end < begin) { fprintf (stderr, "%s:%u: src=\"%s\", clipBegin>clipEnd: %u>%u\n", smil, lineno, dvname, begin, end); return 1; } f = fopen (dvname, "rbm"); if (!f) { fprintf (stderr, "%s:%u: cannot open %s: %m\n", smil, lineno, dvname); return 2; } if (4 != fread (frame, 1, 4, f)) { freadError: if (feof (f)) { fprintf (stderr, "%s:%u: unexpected end of file %s at %u frames\n", smil, lineno, dvname, curr); return 0; } else fprintf (stderr, "%s:%u: reading frame %u from %s: %m\n", smil, lineno, curr, dvname); fclose (f); return 2; } if (memcmp (frame, "\037\7", 3)) { fprintf (stderr, "%s:%u: file %s is not in DIF format\n", smil, lineno, dvname); fclose (f); return 3; } /* * Determine the number of bytes per frame, * assuming that all frames in the file are in the same format. */ if (!(frame[3] & 0x80)) framelen = 120000; /* NTSC format */ /* skip the first frames by seeking, fall back to reading */ if (!fseeko (f, (off_t) framelen * begin, SEEK_SET)) curr = begin; else { if (framelen - 4 != fread (frame + 4, 1, framelen - 4, f)) goto freadError; while (++curr <= begin) if (framelen != fread (frame, 1, framelen, f)) goto freadError; goto writeFrame; } /* copy frames until end of file */ while (curr <= end) { if (framelen != fread (frame, 1, framelen, f)) goto freadError; curr++; writeFrame: if (framelen != write (STDOUT_FILENO, frame, framelen)) { fprintf (stderr, "%s:%u: writing frame %u of %s: %m\n", smil, lineno, curr, dvname); fclose (f); return 4; } } fclose (f); return 0; } /** The main program. * Read the SMIL files specified as command line arguments and output * the referred DV streams on standard output. * @param argc number of command line arguments * @param argv the command line arguments */ int main (int argc, char** argv) { char** arg; /** string buffer */ char* buf = malloc (16); /** allocated length of buf */ unsigned buflen = 16; for (arg = argv; ++arg != argv + argc; ) { FILE* f = fopen (*arg, "rt"); if (!f) { fprintf (stderr, "%s: fopen (\"%s\"): %m\n", *argv, *arg); free (buf); return 1; } else { /** current line number */ unsigned lineno = 1; /** lexer state */ enum { Normal, Tag, Attr, Equals, Quote } state = Normal; /** string being captured (same order as attrs[] below) */ enum { sSrc, sBegin, sEnd, sNone } capture = sNone; /** video source file (pointer to last character, or 0 if not reading) */ char* src = 0; /** begin frame */ unsigned begin = UINT_MAX; /** end frame */ unsigned end = UINT_MAX; /** the tag to look for */ static const char* const tag = "video"; /** next expected character of the magic tag (0=no match) */ const char* tnext = 0; /** the attributes to look for */ static const char* const attrs[] = { "src", "clipBegin", "clipEnd", 0 }; /** next expected characters of the attributes */ const char* anext[sizeof (attrs) / sizeof *attrs - 1]; while (f) { int c = getc (f); switch (c) { case EOF: if (state) fprintf (stderr, "%s:%u: unexpected end of file\n", *arg, lineno); fclose (f), f = 0; continue; /* to do: process XML entities < >, &, ", etc. case '&': ...; break; case ';': ...; break; */ case '=': switch (state) { case Normal: break; case Quote: goto append; case Tag: case Equals: fprintf (stderr, "%s:%u: unexpected '='\n", *arg, lineno); tnext = 0; /* fall through */ case Attr: state = Equals; break; } break; case '"': capture = sNone; switch (state) { case Normal: break; case Tag: case Attr: fprintf (stderr, "%s:%u: unexpected '\"'\n", *arg, lineno); state = Quote; tnext = 0; src = 0; break; case Equals: if (tnext && !*tnext) { unsigned a; for (a = 0; attrs[a]; a++) if (anext[a] && !*anext[a]) capture = a; switch (capture) { case sNone: break; case sSrc: src = 0; break; case sBegin: begin = UINT_MAX; break; case sEnd: end = UINT_MAX; break; } } state = Quote; break; case Quote: state = Attr; memcpy (anext, attrs, sizeof anext); break; } break; case '<': if (state != Normal) fprintf (stderr, "%s:%u: '<' without '>'\n", *arg, lineno); state = Tag; tnext = tag; break; case '>': if (state == Quote) fprintf (stderr, "%s:%u: unterminated '\"' before '>'\n", *arg, lineno); else if (src && begin != UINT_MAX && end != UINT_MAX) { *src = 0; if (dvread (*arg, lineno, buf, begin, end)) { free (buf); fclose (f); return 2; } } state = Normal; tnext = 0; src = 0; begin = UINT_MAX; end = UINT_MAX; break; case '\n': lineno++; case '\v': case '\f': case '\t': case ' ': switch (state) { case Normal: case Attr: case Equals: break; case Quote: goto append; case Tag: if (tnext != tag) { /* got a non-whitespace character after '<' */ state = Attr; memcpy (anext, attrs, sizeof anext); } } break; case '\0': fprintf (stderr, "%s: %u: ignoring NUL character\n", *arg, lineno); break; default: switch (state) { case Tag: if (tnext && (char) (unsigned char) c != *tnext++) tnext = 0; break; case Attr: if (tnext && !*tnext) { unsigned a; for (a = 0; attrs[a]; a++) if (anext[a] && (char) (unsigned char) c != *anext[a]++) anext[a] = 0; } break; case Normal: case Equals: break; case Quote: append: switch (capture) { case sNone: break; case sSrc: if (!src) src = buf; *src++ = c; if (src == buf + buflen) { buf = realloc (buf, buflen << 1); src = buf + buflen; buflen <<= 1; } break; case sBegin: if (c < '0' || c > '9') fprintf (stderr, "%s: %u: ignoring '%c' in clipBegin\n", *arg, lineno, (unsigned char) c); else if (begin == UINT_MAX) begin = c - '0'; else begin *= 10, begin += c - '0'; break; case sEnd: if (c < '0' || c > '9') fprintf (stderr, "%s: %u: ignoring '%c' in clipEnd\n", *arg, lineno, (unsigned char) c); else if (end == UINT_MAX) end = c - '0'; else end *= 10, end += c - '0'; break; } break; } } } } } free (buf); return 0; }