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- #include <u.h>
- #include <libc.h>
- #include <bio.h>
- #include <ctype.h>
- #include <mach.h>
- /*
- * file - determine type of file
- */
- #define LENDIAN(p) ((p)[0] | ((p)[1]<<8) | ((p)[2]<<16) | ((p)[3]<<24))
- uchar buf[6001];
- short cfreq[140];
- short wfreq[50];
- int nbuf;
- Dir* mbuf;
- int fd;
- char *fname;
- char *slash;
- enum
- {
- Cword,
- Fword,
- Aword,
- Alword,
- Lword,
- I1,
- I2,
- I3,
- Clatin = 128,
- Cbinary,
- Cnull,
- Ceascii,
- Cutf,
- };
- struct
- {
- char* word;
- int class;
- } dict[] =
- {
- "PATH", Lword,
- "TEXT", Aword,
- "adt", Alword,
- "aggr", Alword,
- "alef", Alword,
- "array", Lword,
- "block", Fword,
- "chan", Alword,
- "char", Cword,
- "common", Fword,
- "con", Lword,
- "data", Fword,
- "dimension", Fword,
- "double", Cword,
- "extern", Cword,
- "bio", I2,
- "float", Cword,
- "fn", Lword,
- "function", Fword,
- "h", I3,
- "implement", Lword,
- "import", Lword,
- "include", I1,
- "int", Cword,
- "integer", Fword,
- "iota", Lword,
- "libc", I2,
- "long", Cword,
- "module", Lword,
- "real", Fword,
- "ref", Lword,
- "register", Cword,
- "self", Lword,
- "short", Cword,
- "static", Cword,
- "stdio", I2,
- "struct", Cword,
- "subroutine", Fword,
- "u", I2,
- "void", Cword,
- };
- /* codes for 'mode' field in language structure */
- enum {
- Normal = 0,
- First, /* first entry for language spanning several ranges */
- Multi, /* later entries " " " ... */
- Shared, /* codes used in several languages */
- };
- struct
- {
- int mode; /* see enum above */
- int count;
- int low;
- int high;
- char *name;
-
- } language[] =
- {
- Normal, 0, 0x0080, 0x0080, "Extended Latin",
- Normal, 0, 0x0100, 0x01FF, "Extended Latin",
- Normal, 0, 0x0370, 0x03FF, "Greek",
- Normal, 0, 0x0400, 0x04FF, "Cyrillic",
- Normal, 0, 0x0530, 0x058F, "Armenian",
- Normal, 0, 0x0590, 0x05FF, "Hebrew",
- Normal, 0, 0x0600, 0x06FF, "Arabic",
- Normal, 0, 0x0900, 0x097F, "Devanagari",
- Normal, 0, 0x0980, 0x09FF, "Bengali",
- Normal, 0, 0x0A00, 0x0A7F, "Gurmukhi",
- Normal, 0, 0x0A80, 0x0AFF, "Gujarati",
- Normal, 0, 0x0B00, 0x0B7F, "Oriya",
- Normal, 0, 0x0B80, 0x0BFF, "Tamil",
- Normal, 0, 0x0C00, 0x0C7F, "Telugu",
- Normal, 0, 0x0C80, 0x0CFF, "Kannada",
- Normal, 0, 0x0D00, 0x0D7F, "Malayalam",
- Normal, 0, 0x0E00, 0x0E7F, "Thai",
- Normal, 0, 0x0E80, 0x0EFF, "Lao",
- Normal, 0, 0x1000, 0x105F, "Tibetan",
- Normal, 0, 0x10A0, 0x10FF, "Georgian",
- Normal, 0, 0x3040, 0x30FF, "Japanese",
- Normal, 0, 0x3100, 0x312F, "Chinese",
- First, 0, 0x3130, 0x318F, "Korean",
- Multi, 0, 0x3400, 0x3D2F, "Korean",
- Shared, 0, 0x4e00, 0x9fff, "CJK",
- Normal, 0, 0, 0, 0, /* terminal entry */
- };
-
-
- enum
- {
- Fascii, /* printable ascii */
- Flatin, /* latin 1*/
- Futf, /* UTf character set */
- Fbinary, /* binary */
- Feascii, /* ASCII with control chars */
- Fnull, /* NULL in file */
- } guess;
- void bump_utf_count(Rune);
- int cistrncmp(char*, char*, int);
- void filetype(int);
- int getfontnum(uchar*, uchar**);
- int isas(void);
- int isc(void);
- int iscint(void);
- int isenglish(void);
- int ishp(void);
- int ishtml(void);
- int isrfc822(void);
- int ismbox(void);
- int islimbo(void);
- int ismung(void);
- int isp9bit(void);
- int isp9font(void);
- int istring(void);
- int long0(void);
- int p9bitnum(uchar*);
- int p9subfont(uchar*);
- void print_utf(void);
- void type(char*, int);
- int utf_count(void);
- void wordfreq(void);
- int (*call[])(void) =
- {
- long0, /* recognizable by first 4 bytes */
- istring, /* recognizable by first string */
- ishtml, /* html keywords */
- isrfc822, /* email file */
- ismbox, /* mail box */
- iscint, /* compiler/assembler intermediate */
- islimbo, /* limbo source */
- isc, /* c & alef compiler key words */
- isas, /* assembler key words */
- ismung, /* entropy compressed/encrypted */
- isp9font, /* plan 9 font */
- isp9bit, /* plan 9 image (as from /dev/window) */
- isenglish, /* char frequency English */
- ishp, /* HP Job Control Language - Postscript */
- 0
- };
- int mime;
- #define OCTET "application/octet-stream\n"
- #define PLAIN "text/plain\n"
- void
- main(int argc, char *argv[])
- {
- int i, j, maxlen;
- char *cp;
- Rune r;
- ARGBEGIN{
- case 'm':
- mime = 1;
- break;
- default:
- fprint(2, "usage: file [-m] [file...]\n");
- exits("usage");
- }ARGEND;
- maxlen = 0;
- if(mime == 0 || argc > 1){
- for(i = 0; i < argc; i++) {
- for (j = 0, cp = argv[i]; *cp; j++, cp += chartorune(&r, cp))
- ;
- if(j > maxlen)
- maxlen = j;
- }
- }
- if (argc <= 0) {
- if(!mime)
- print ("stdin: ");
- filetype(0);
- }
- else {
- for(i = 0; i < argc; i++)
- type(argv[i], maxlen);
- }
- exits(0);
- }
- void
- type(char *file, int nlen)
- {
- Rune r;
- int i;
- char *p;
- if(nlen > 0){
- slash = 0;
- for (i = 0, p = file; *p; i++) {
- if (*p == '/') /* find rightmost slash */
- slash = p;
- p += chartorune(&r, p); /* count runes */
- }
- print("%s:%*s",file, nlen-i+1, "");
- }
- fname = file;
- if ((fd = open(file, OREAD)) < 0) {
- print("cannot open\n");
- return;
- }
- filetype(fd);
- close(fd);
- }
- void
- filetype(int fd)
- {
- Rune r;
- int i, f, n;
- char *p, *eob;
- free(mbuf);
- mbuf = dirfstat(fd);
- if(mbuf == nil){
- print("cannot stat: %r\n");
- return;
- }
- if(mbuf->mode & DMDIR) {
- print(mime ? "text/directory\n" : "directory\n");
- return;
- }
- if(mbuf->type != 'M' && mbuf->type != '|') {
- print(mime ? OCTET : "special file #%c/%s\n",
- mbuf->type, mbuf->name);
- return;
- }
- nbuf = read(fd, buf, sizeof(buf)-1);
- if(nbuf < 0) {
- print("cannot read\n");
- return;
- }
- if(nbuf == 0) {
- print(mime ? PLAIN : "empty file\n");
- return;
- }
- buf[nbuf] = 0;
- /*
- * build histogram table
- */
- memset(cfreq, 0, sizeof(cfreq));
- for (i = 0; language[i].name; i++)
- language[i].count = 0;
- eob = (char *)buf+nbuf;
- for(n = 0, p = (char *)buf; p < eob; n++) {
- if (!fullrune(p, eob-p) && eob-p < UTFmax)
- break;
- p += chartorune(&r, p);
- if (r == 0)
- f = Cnull;
- else if (r <= 0x7f) {
- if (!isprint(r) && !isspace(r))
- f = Ceascii; /* ASCII control char */
- else f = r;
- } else if (r == 0x080) {
- bump_utf_count(r);
- f = Cutf;
- } else if (r < 0xA0)
- f = Cbinary; /* Invalid Runes */
- else if (r <= 0xff)
- f = Clatin; /* Latin 1 */
- else {
- bump_utf_count(r);
- f = Cutf; /* UTF extension */
- }
- cfreq[f]++; /* ASCII chars peg directly */
- }
- /*
- * gross classify
- */
- if (cfreq[Cbinary])
- guess = Fbinary;
- else if (cfreq[Cutf])
- guess = Futf;
- else if (cfreq[Clatin])
- guess = Flatin;
- else if (cfreq[Ceascii])
- guess = Feascii;
- else if (cfreq[Cnull] == n) {
- print(mime ? OCTET : "first block all null bytes\n");
- return;
- }
- else guess = Fascii;
- /*
- * lookup dictionary words
- */
- memset(wfreq, 0, sizeof(wfreq));
- if(guess == Fascii || guess == Flatin || guess == Futf)
- wordfreq();
- /*
- * call individual classify routines
- */
- for(i=0; call[i]; i++)
- if((*call[i])())
- return;
- /*
- * if all else fails,
- * print out gross classification
- */
- if (nbuf < 100 && !mime)
- print(mime ? PLAIN : "short ");
- if (guess == Fascii)
- print(mime ? PLAIN : "Ascii\n");
- else if (guess == Feascii)
- print(mime ? PLAIN : "extended ascii\n");
- else if (guess == Flatin)
- print(mime ? PLAIN : "latin ascii\n");
- else if (guess == Futf && utf_count() < 4)
- print_utf();
- else print(mime ? OCTET : "binary\n");
- }
- void
- bump_utf_count(Rune r)
- {
- int low, high, mid;
- high = sizeof(language)/sizeof(language[0])-1;
- for (low = 0; low < high;) {
- mid = (low+high)/2;
- if (r >=language[mid].low) {
- if (r <= language[mid].high) {
- language[mid].count++;
- break;
- } else low = mid+1;
- } else high = mid;
- }
- }
- int
- utf_count(void)
- {
- int i, count;
- count = 0;
- for (i = 0; language[i].name; i++)
- if (language[i].count > 0)
- switch (language[i].mode) {
- case Normal:
- case First:
- count++;
- break;
- default:
- break;
- }
- return count;
- }
- int
- chkascii(void)
- {
- int i;
- for (i = 'a'; i < 'z'; i++)
- if (cfreq[i])
- return 1;
- for (i = 'A'; i < 'Z'; i++)
- if (cfreq[i])
- return 1;
- return 0;
- }
- int
- find_first(char *name)
- {
- int i;
- for (i = 0; language[i].name != 0; i++)
- if (language[i].mode == First
- && strcmp(language[i].name, name) == 0)
- return i;
- return -1;
- }
- void
- print_utf(void)
- {
- int i, printed, j;
- if(mime){
- print(PLAIN);
- return;
- }
- if (chkascii()) {
- printed = 1;
- print("Ascii");
- } else
- printed = 0;
- for (i = 0; language[i].name; i++)
- if (language[i].count) {
- switch(language[i].mode) {
- case Multi:
- j = find_first(language[i].name);
- if (j < 0)
- break;
- if (language[j].count > 0)
- break;
- /* Fall through */
- case Normal:
- case First:
- if (printed)
- print(" & ");
- else printed = 1;
- print("%s", language[i].name);
- break;
- case Shared:
- default:
- break;
- }
- }
- if(!printed)
- print("UTF");
- print(" text\n");
- }
- void
- wordfreq(void)
- {
- int low, high, mid, r;
- uchar *p, *p2, c;
- p = buf;
- for(;;) {
- while (p < buf+nbuf && !isalpha(*p))
- p++;
- if (p >= buf+nbuf)
- return;
- p2 = p;
- while(p < buf+nbuf && isalpha(*p))
- p++;
- c = *p;
- *p = 0;
- high = sizeof(dict)/sizeof(dict[0]);
- for(low = 0;low < high;) {
- mid = (low+high)/2;
- r = strcmp(dict[mid].word, (char*)p2);
- if(r == 0) {
- wfreq[dict[mid].class]++;
- break;
- }
- if(r < 0)
- low = mid+1;
- else
- high = mid;
- }
- *p++ = c;
- }
- }
- typedef struct Filemagic Filemagic;
- struct Filemagic {
- ulong x;
- ulong mask;
- char *desc;
- char *mime;
- };
- Filemagic long0tab[] = {
- 0xF16DF16D, 0xFFFFFFFF, "pac1 audio file\n", OCTET,
- 0x31636170, 0xFFFFFFFF, "pac3 audio file\n", OCTET,
- 0x32636170, 0xFFFF00FF, "pac4 audio file\n", OCTET,
- 0xBA010000, 0xFFFFFFFF, "mpeg system stream\n", OCTET,
- 0x30800CC0, 0xFFFFFFFF, "inferno .dis executable\n", OCTET,
- 0x04034B50, 0xFFFFFFFF, "zip archive\n", OCTET,
- 070707, 0xFFFF, "cpio archive\n", OCTET,
- 0x2F7, 0xFFFF, "tex dvi\n", OCTET,
- };
- int
- filemagic(Filemagic *tab, int ntab, ulong x)
- {
- int i;
- for(i=0; i<ntab; i++)
- if((x&tab[i].mask) == tab[i].x){
- print(mime ? tab[i].mime : tab[i].desc);
- return 1;
- }
- return 0;
- }
-
- int
- long0(void)
- {
- Fhdr f;
- long x;
- seek(fd, 0, 0); /* reposition to start of file */
- if(crackhdr(fd, &f)) {
- print(mime ? OCTET : "%s\n", f.name);
- return 1;
- }
- x = LENDIAN(buf);
- if(filemagic(long0tab, nelem(long0tab), x))
- return 1;
- return 0;
- }
- /*
- * initial words to classify file
- */
- struct FILE_STRING
- {
- char *key;
- char *filetype;
- int length;
- char *mime;
- } file_string[] =
- {
- "!<arch>\n__.SYMDEF", "archive random library", 16, "application/octet-stream",
- "!<arch>\n", "archive", 8, "application/octet-stream",
- "070707", "cpio archive - ascii header", 6, "application/octet-stream",
- "#!/bin/rc", "rc executable file", 9, "text/plain",
- "#!/bin/sh", "sh executable file", 9, "text/plain",
- "%!", "postscript", 2, "application/postscript",
- "\004%!", "postscript", 3, "application/postscript",
- "x T post", "troff output for post", 8, "application/troff",
- "x T Latin1", "troff output for Latin1", 10, "application/troff",
- "x T utf", "troff output for UTF", 7, "application/troff",
- "x T 202", "troff output for 202", 7, "application/troff",
- "x T aps", "troff output for aps", 7, "application/troff",
- "GIF", "GIF image", 3, "image/gif",
- "\0PC Research, Inc\0", "ghostscript fax file", 18, "application/ghostscript",
- "%PDF", "PDF", 4, "application/pdf",
- "<html>\n", "HTML file", 7, "text/html",
- "<HTML>\n", "HTML file", 7, "text/html",
- "compressed\n", "Compressed image or subfont", 11, "application/octet-stream",
- "\111\111\052\000", "tiff", 4, "image/tiff",
- "\115\115\000\052", "tiff", 4, "image/tiff",
- "\377\330\377\340", "jpeg", 4, "image/jpeg",
- "\377\330\377\341", "jpeg", 4, "image/jpeg",
- "\377\330\377\333", "jpeg", 4, "image/jpeg",
- "\xD0\xCF\x11\xE0\xA1\xB1\x1A\xE1", "microsoft office document", 8, "application/octet-stream",
- 0,0,0,0
- };
- int
- istring(void)
- {
- int i;
- struct FILE_STRING *p;
- for(p = file_string; p->key; p++) {
- if(nbuf >= p->length && !memcmp(buf, p->key, p->length)) {
- if(mime)
- print("%s\n", p->mime);
- else
- print("%s\n", p->filetype);
- return 1;
- }
- }
- if(strncmp((char*)buf, "TYPE=", 5) == 0) { /* td */
- for(i = 5; i < nbuf; i++)
- if(buf[i] == '\n')
- break;
- if(mime)
- print(OCTET);
- else
- print("%.*s picture\n", utfnlen((char*)buf+5, i-5), (char*)buf+5);
- return 1;
- }
- return 0;
- }
- char* html_string[] =
- {
- "title",
- "body",
- "head",
- "strong",
- "h1",
- "h2",
- "h3",
- "h4",
- "h5",
- "h6",
- "ul",
- "li",
- "dl",
- "br",
- "em",
- 0,
- };
- int
- ishtml(void)
- {
- uchar *p, *q;
- int i, count;
- /* compare strings between '<' and '>' to html table */
- count = 0;
- p = buf;
- for(;;) {
- while (p < buf+nbuf && *p != '<')
- p++;
- p++;
- if (p >= buf+nbuf)
- break;
- if(*p == '/')
- p++;
- q = p;
- while(p < buf+nbuf && *p != '>')
- p++;
- if (p >= buf+nbuf)
- break;
- for(i = 0; html_string[i]; i++) {
- if(cistrncmp(html_string[i], (char*)q, p-q) == 0) {
- if(count++ > 4) {
- print(mime ? "text/html\n" : "HTML file\n");
- return 1;
- }
- break;
- }
- }
- p++;
- }
- return 0;
- }
- char* rfc822_string[] =
- {
- "from:",
- "date:",
- "to:",
- "subject:",
- "received:",
- "reply to:",
- "sender:",
- 0,
- };
- int
- isrfc822(void)
- {
- char *p, *q, *r;
- int i, count;
- count = 0;
- p = (char*)buf;
- for(;;) {
- q = strchr(p, '\n');
- if(q == nil)
- break;
- *q = 0;
- if(p == (char*)buf && strncmp(p, "From ", 5) == 0 && strstr(p, " remote from ")){
- count++;
- *q = '\n';
- p = q+1;
- continue;
- }
- *q = '\n';
- if(*p != '\t' && *p != ' '){
- r = strchr(p, ':');
- if(r == 0 || r > q)
- break;
- for(i = 0; rfc822_string[i]; i++) {
- if(cistrncmp(p, rfc822_string[i], strlen(rfc822_string[i])) == 0){
- count++;
- break;
- }
- }
- }
- p = q+1;
- }
- if(count >= 3){
- print(mime ? "message/rfc822\n" : "email file\n");
- return 1;
- }
- return 0;
- }
- int
- ismbox(void)
- {
- char *p, *q;
- p = (char*)buf;
- q = strchr(p, '\n');
- if(q == nil)
- return 0;
- *q = 0;
- if(strncmp(p, "From ", 5) == 0 && strstr(p, " remote from ") == nil){
- print(mime ? "text/plain\n" : "mail box\n");
- return 1;
- }
- *q = '\n';
- return 0;
- }
- int
- iscint(void)
- {
- int type;
- char *name;
- Biobuf b;
- if(Binit(&b, fd, OREAD) == Beof)
- return 0;
- seek(fd, 0, 0);
- type = objtype(&b, &name);
- if(type < 0)
- return 0;
- if(mime)
- print(OCTET);
- else
- print("%s intermediate\n", name);
- return 1;
- }
- int
- isc(void)
- {
- int n;
- n = wfreq[I1];
- /*
- * includes
- */
- if(n >= 2 && wfreq[I2] >= n && wfreq[I3] >= n && cfreq['.'] >= n)
- goto yes;
- if(n >= 1 && wfreq[Alword] >= n && wfreq[I3] >= n && cfreq['.'] >= n)
- goto yes;
- /*
- * declarations
- */
- if(wfreq[Cword] >= 5 && cfreq[';'] >= 5)
- goto yes;
- /*
- * assignments
- */
- if(cfreq[';'] >= 10 && cfreq['='] >= 10 && wfreq[Cword] >= 1)
- goto yes;
- return 0;
- yes:
- if(mime){
- print(PLAIN);
- return 1;
- }
- if(wfreq[Alword] > 0)
- print("alef program\n");
- else
- print("c program\n");
- return 1;
- }
- int
- islimbo(void)
- {
- /*
- * includes
- */
- if(wfreq[Lword] < 4)
- return 0;
- print(mime ? PLAIN : "limbo program\n");
- return 1;
- }
- int
- isas(void)
- {
- /*
- * includes
- */
- if(wfreq[Aword] < 2)
- return 0;
- print(mime ? PLAIN : "as program\n");
- return 1;
- }
- /*
- * low entropy means encrypted
- */
- int
- ismung(void)
- {
- int i, bucket[8];
- float cs;
- if(nbuf < 64)
- return 0;
- memset(bucket, 0, sizeof(bucket));
- for(i=0; i<64; i++)
- bucket[(buf[i]>>5)&07] += 1;
- cs = 0.;
- for(i=0; i<8; i++)
- cs += (bucket[i]-8)*(bucket[i]-8);
- cs /= 8.;
- if(cs <= 24.322) {
- if(buf[0]==0x1f && (buf[1]==0x8b || buf[1]==0x9d))
- print(mime ? OCTET : "compressed\n");
- else
- print(mime ? OCTET : "encrypted\n");
- return 1;
- }
- return 0;
- }
- /*
- * english by punctuation and frequencies
- */
- int
- isenglish(void)
- {
- int vow, comm, rare, badpun, punct;
- char *p;
- if(guess != Fascii && guess != Feascii)
- return 0;
- badpun = 0;
- punct = 0;
- for(p = (char *)buf; p < (char *)buf+nbuf-1; p++)
- switch(*p) {
- case '.':
- case ',':
- case ')':
- case '%':
- case ';':
- case ':':
- case '?':
- punct++;
- if(p[1] != ' ' && p[1] != '\n')
- badpun++;
- }
- if(badpun*5 > punct)
- return 0;
- if(cfreq['>']+cfreq['<']+cfreq['/'] > cfreq['e']) /* shell file test */
- return 0;
- if(2*cfreq[';'] > cfreq['e'])
- return 0;
- vow = 0;
- for(p="AEIOU"; *p; p++) {
- vow += cfreq[*p];
- vow += cfreq[tolower(*p)];
- }
- comm = 0;
- for(p="ETAION"; *p; p++) {
- comm += cfreq[*p];
- comm += cfreq[tolower(*p)];
- }
- rare = 0;
- for(p="VJKQXZ"; *p; p++) {
- rare += cfreq[*p];
- rare += cfreq[tolower(*p)];
- }
- if(vow*5 >= nbuf-cfreq[' '] && comm >= 10*rare) {
- print(mime ? PLAIN : "English text\n");
- return 1;
- }
- return 0;
- }
- /*
- * pick up a number with
- * syntax _*[0-9]+_
- */
- #define P9BITLEN 12
- int
- p9bitnum(uchar *bp)
- {
- int n, c, len;
- len = P9BITLEN;
- while(*bp == ' ') {
- bp++;
- len--;
- if(len <= 0)
- return -1;
- }
- n = 0;
- while(len > 1) {
- c = *bp++;
- if(!isdigit(c))
- return -1;
- n = n*10 + c-'0';
- len--;
- }
- if(*bp != ' ')
- return -1;
- return n;
- }
- int
- depthof(char *s, int *newp)
- {
- char *es;
- int d;
- *newp = 0;
- es = s+12;
- while(s<es && *s==' ')
- s++;
- if(s == es)
- return -1;
- if('0'<=*s && *s<='9')
- return 1<<atoi(s);
- *newp = 1;
- d = 0;
- while(s<es && *s!=' '){
- s++; /* skip letter */
- d += strtoul(s, &s, 10);
- }
-
- switch(d){
- case 32:
- case 24:
- case 16:
- case 8:
- return d;
- }
- return -1;
- }
- int
- isp9bit(void)
- {
- int dep, lox, loy, hix, hiy, px, new;
- ulong t;
- long len;
- char *newlabel;
- newlabel = "old ";
- dep = depthof((char*)buf + 0*P9BITLEN, &new);
- if(new)
- newlabel = "";
- lox = p9bitnum(buf + 1*P9BITLEN);
- loy = p9bitnum(buf + 2*P9BITLEN);
- hix = p9bitnum(buf + 3*P9BITLEN);
- hiy = p9bitnum(buf + 4*P9BITLEN);
- if(dep < 0 || lox < 0 || loy < 0 || hix < 0 || hiy < 0)
- return 0;
- if(dep < 8){
- px = 8/dep; /* pixels per byte */
- /* set l to number of bytes of data per scan line */
- if(lox >= 0)
- len = (hix+px-1)/px - lox/px;
- else{ /* make positive before divide */
- t = (-lox)+px-1;
- t = (t/px)*px;
- len = (t+hix+px-1)/px;
- }
- }else
- len = (hix-lox)*dep/8;
- len *= (hiy-loy); /* col length */
- len += 5*P9BITLEN; /* size of initial ascii */
- /*
- * for image file, length is non-zero and must match calculation above
- * for /dev/window and /dev/screen the length is always zero
- * for subfont, the subfont header should follow immediately.
- */
- if (len != 0 && mbuf->length == 0) {
- print("%splan 9 image\n", newlabel);
- return 1;
- }
- if (mbuf->length == len) {
- print("%splan 9 image\n", newlabel);
- return 1;
- }
- /* Ghostscript sometimes produces a little extra on the end */
- if (mbuf->length < len+P9BITLEN) {
- print("%splan 9 image\n", newlabel);
- return 1;
- }
- if (p9subfont(buf+len)) {
- print("%ssubfont file\n", newlabel);
- return 1;
- }
- return 0;
- }
- int
- p9subfont(uchar *p)
- {
- int n, h, a;
- /* if image too big, assume it's a subfont */
- if (p+3*P9BITLEN > buf+sizeof(buf))
- return 1;
- n = p9bitnum(p + 0*P9BITLEN); /* char count */
- if (n < 0)
- return 0;
- h = p9bitnum(p + 1*P9BITLEN); /* height */
- if (h < 0)
- return 0;
- a = p9bitnum(p + 2*P9BITLEN); /* ascent */
- if (a < 0)
- return 0;
- return 1;
- }
- #define WHITESPACE(c) ((c) == ' ' || (c) == '\t' || (c) == '\n')
- int
- isp9font(void)
- {
- uchar *cp, *p;
- int i, n;
- char pathname[1024];
- cp = buf;
- if (!getfontnum(cp, &cp)) /* height */
- return 0;
- if (!getfontnum(cp, &cp)) /* ascent */
- return 0;
- for (i = 0; 1; i++) {
- if (!getfontnum(cp, &cp)) /* min */
- break;
- if (!getfontnum(cp, &cp)) /* max */
- return 0;
- while (WHITESPACE(*cp))
- cp++;
- for (p = cp; *cp && !WHITESPACE(*cp); cp++)
- ;
- /* construct a path name, if needed */
- n = 0;
- if (*p != '/' && slash) {
- n = slash-fname+1;
- if (n < sizeof(pathname))
- memcpy(pathname, fname, n);
- else n = 0;
- }
- if (n+cp-p < sizeof(pathname)) {
- memcpy(pathname+n, p, cp-p);
- n += cp-p;
- pathname[n] = 0;
- if (access(pathname, AEXIST) < 0)
- return 0;
- }
- }
- if (i) {
- print("font file\n");
- return 1;
- }
- return 0;
- }
- int
- getfontnum(uchar *cp, uchar **rp)
- {
- while (WHITESPACE(*cp)) /* extract ulong delimited by whitespace */
- cp++;
- if (*cp < '0' || *cp > '9')
- return 0;
- strtoul((char *)cp, (char **)rp, 0);
- if (!WHITESPACE(**rp))
- return 0;
- return 1;
- }
- int
- ishp(void)
- {
- if (strncmp("\033%-12345X", (char *)buf, 9)==0) {
- print("HPJCL file\n");
- return 1;
- }
- return 0;
- }
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