X-Git-Url: https://git.distorted.org.uk/~mdw/sgt/halibut/blobdiff_plain/44407fea05657f91da34fd83428b67e7100ab62b..2901c406fda763902b1e77263ec273187f7dc75b:/in_pf.c

diff --git a/in_pf.c b/in_pf.c
index 50e663e..8f7a4ac 100644
--- a/in_pf.c
+++ b/in_pf.c
@@ -1,34 +1,453 @@
+/*
+ * PostScript Type 1 font file support for Halibut
+ */
+/*
+ * Type 1 font file formats are specified by Adobe Technical Note
+ * #5040: "Supporting Downloadable PostScript Language Fonts".
+ * Halibut supports hexadecimal format (section 3.1) and IBM PC format
+ * (section 3.3), commonly called PFA and PFB respectively.
+ */
+
+#include <assert.h>
+#include <limits.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include "halibut.h"
 #include "paper.h"
 
+#define PFB_ASCII	1
+#define PFB_BINARY	2
+#define PFB_EOF		3
+
+typedef struct t1_font_Tag t1_font;
+typedef struct t1_data_Tag t1_data;
+
+struct t1_font_Tag {
+    t1_data *data;
+    size_t length1;
+    size_t length2;
+    filepos pos;
+};
+
+struct t1_data_Tag {
+    char type;
+    size_t length;
+    unsigned char *data;
+    t1_data *next;
+};
+
+typedef struct pfstate_Tag {
+    t1_data *data;
+    t1_data *curblock;
+    size_t offset;
+} pfstate;
+
+static void pf_identify(t1_font *tf);
+
+static t1_data *load_pfb_file(FILE *fp, filepos *pos) {
+    t1_data *head = NULL, *tail = NULL;
+    int c, i;
+    char type;
+
+    pos->line = 0;
+    for (;;) {
+	if (fgetc(fp) != 128) abort();
+	type = fgetc(fp);
+	if (type == PFB_EOF) return head;
+	if (tail) {
+	    tail->next = snew(t1_data);
+	    tail = tail->next;
+	} else {
+	    head = snew(t1_data);
+	    tail = head;
+	}
+	tail->type = type;
+	tail->length = 0;
+	for (i = 0; i < 4; i++) {
+	    c = fgetc(fp);
+	    if (c == EOF) abort();
+	    tail->length |= c << (8 * i);
+	}
+	tail->data = snewn(tail->length, unsigned char);
+	if (fread(tail->data, 1, tail->length, fp) != tail->length) abort();
+    }
+    tail->next = NULL;
+}
+
+static t1_data *load_pfa_file(FILE *fp, filepos *pos) {
+    t1_data *ret = snew(t1_data);
+    size_t off = 0, len, got;
+
+    pos->line = 0;
+    ret->type = PFB_ASCII;
+    len = 32768;
+    ret->data = snewn(len, unsigned char);
+    for (;;) {
+	got = fread(ret->data + off, 1, len - off, fp);
+	off += got;
+	if (off != len) break;
+	len *= 2;
+	ret->data = sresize(ret->data, len, unsigned char);
+    }
+    ret->data = sresize(ret->data, off, unsigned char);
+    ret->length = off;
+    ret->next = NULL;
+    return ret;
+}
+
 void read_pfa_file(input *in) {
-    char buf[512], *p;
+    t1_font *tf = snew(t1_font);
+
+    tf->data = load_pfa_file(in->currfp, &in->pos);
+    tf->pos = in->pos;
+    tf->length1 = tf->length2 = 0;
+    fclose(in->currfp);
+    pf_identify(tf);
+}
+
+void read_pfb_file(input *in) {
+    t1_font *tf = snew(t1_font);
+
+    tf->data = load_pfb_file(in->currfp, &in->pos);
+    tf->pos = in->pos;
+    tf->length1 = tf->length2 = 0;
+    fclose(in->currfp);
+    pf_identify(tf);
+}
+static char *pf_read_token(pfstate *);
+
+/*
+ * Read a character from the initial plaintext part of a Type 1 font
+ */
+static int pf_getc(pfstate *pf) {
+    if (pf->offset == pf->curblock->length) {
+	if (pf->curblock->next == NULL) return EOF;
+	pf->curblock = pf->curblock->next;
+	pf->offset = 0;
+    }
+    if (pf->curblock->type != PFB_ASCII) return EOF;
+    return pf->curblock->data[pf->offset++];
+}
+
+static void pf_ungetc(int c, pfstate *pf) {
+    assert(pf->offset > 0);
+    pf->offset--;
+    assert(c == pf->curblock->data[pf->offset]);
+}
+
+static void pf_rewind(pfstate *pf) {
+    pf->curblock = pf->data;
+    pf->offset = 0;
+}
+
+static void pf_seek(pfstate *pf, size_t off) {
+    t1_data *td = pf->data;
+
+    while (td->length < off) {
+	off -= td->length;
+	td = td->next;
+    }
+    pf->curblock = td;
+    pf->offset = off;
+}
+
+static size_t pf_tell(pfstate *pf) {
+    t1_data *td = pf->data;
+    size_t o = 0;
+
+    while (td != pf->curblock) {
+	o += td->length;
+	td = td->next;
+    }
+    return o + pf->offset;
+}
+
+static void pf_identify(t1_font *tf) {
+    rdstringc rsc = { 0, 0, NULL };
+    char *p;
     size_t len;
     char *fontname;
     font_info *fi;
+    int c;
+    pfstate pfs, *pf = &pfs;
 
-    len = fread(buf, 1, sizeof(buf) - 1, in->currfp);
-    buf[len] = 0;
-    if (strncmp(buf, "%!FontType1-", 12) &&
-	strncmp(buf, "%!PS-AdobeFont-", 15))
+    pf->data = tf->data;
+    pf_rewind(pf);
+    do {
+	c = pf_getc(pf);
+	if (c == EOF) {
+	    sfree(rsc.text);
+	    error(err_pfeof, &tf->pos);
+	    return;
+	}
+	rdaddc(&rsc, c);
+    } while (c != 012 && c != 015);
+    p = rsc.text;
+    if ((p = strchr(p, ':')) == NULL) {
+	sfree(rsc.text);
+	error(err_pfhead, &tf->pos);
 	return;
-    p = buf;
-    p += strcspn(p, ":") + 1;
+    }
+    p++;
     p += strspn(p, " \t");
     len = strcspn(p, " \t");
     fontname = snewn(len + 1, char);
     memcpy(fontname, p, len);
     fontname[len] = 0;
+    sfree(rsc.text);
+
     for (fi = all_fonts; fi; fi = fi->next) {
 	if (strcmp(fi->name, fontname) == 0) {
-	    fi->fp = in->currfp;
+	    fi->fontfile = tf;
+	    fi->filetype = TYPE1;
 	    sfree(fontname);
 	    return;
 	}
     }
-    fclose(in->currfp);
+    error(err_pfnoafm, &tf->pos, fontname);
     sfree(fontname);
 }
-	
-	
+
+/*
+ * PostScript white space characters; PLRM3 table 3.1
+ */
+static int pf_isspace(int c) {
+    return c == 000 || c == 011 || c == 012 || c == 014 || c == 015 ||
+	c == ' ';
+}
+
+/*
+ * PostScript special characters; PLRM3 page 27
+ */
+static int pf_isspecial(int c) {
+    return c == '(' || c == ')' || c == '<' || c == '>' || c == '[' ||
+	c == ']' || c == '{' || c == '}' || c == '/' || c == '%';
+}
+
+static size_t pf_findtoken(t1_font *tf, size_t off, char const *needle) {
+    char *tok;
+    pfstate pfs, *pf = &pfs;
+
+    pf->data = tf->data;
+    pf_seek(pf, off);
+    for (;;) {
+	tok = pf_read_token(pf);
+	if (tok == NULL) {
+	    if (pf->offset == 0 && pf->curblock->type == PFB_BINARY)
+		pf->curblock = pf->curblock->next;
+	    else
+		return (size_t)-1;
+	} else {
+	    if (strcmp(tok, needle) == 0) {
+		sfree(tok);
+		return pf_tell(pf);
+	    }
+	    sfree(tok);
+	}
+    }
+}
+
+static size_t pf_length1(t1_font *tf) {
+    size_t ret;
+
+    ret = pf_findtoken(tf, 0, "eexec");
+    if (ret == (size_t)-1) {
+	error(err_pfeof, &tf->pos);
+	return 0;
+    }
+    return ret;
+}
+
+static size_t pf_length2(t1_font *tf) {
+    size_t ret;
+
+    if (tf->length1 == 0)
+	tf->length1 = pf_length1(tf);
+    ret = pf_findtoken(tf, tf->length1, "cleartomark");
+    if (ret == (size_t)-1) {
+	error(err_pfeof, &tf->pos);
+	return 0;
+    }
+    return ret - 12 - tf->length1; /* backspace over "cleartomark\n" */
+}
+
+static void pf_getascii(t1_font *tf, size_t off, size_t len,
+			char **bufp, size_t *lenp) {
+    t1_data *td = tf->data;
+    size_t blk, i;
+    char *p;
+
+    while (td && off >= td->length) {
+	off -= td->length;
+	td = td->next;
+    }
+    *bufp = NULL;
+    *lenp = 0;
+    while (td && len) {
+	blk = len < td->length ? len : td->length;
+	if (td->type == PFB_ASCII) {
+	    *bufp = sresize(*bufp, *lenp + blk, char);
+	    memcpy(*bufp + *lenp, td->data + off, blk);
+	    *lenp += blk;
+	} else {
+	    *bufp = sresize(*bufp, *lenp + blk * 2 + blk / 39 + 3, char);
+	    p = *bufp + *lenp;
+	    for (i = 0; i < blk; i++) {
+		if (i % 39 == 0) p += sprintf(p, "\n");
+		p += sprintf(p, "%02x", td->data[off + i]);
+	    }
+	    p += sprintf(p, "\n");
+	    *lenp = p - *bufp;
+	}
+	len -= blk;
+	td = td->next;
+	off = 0;
+    }   
+}
+
+void pf_writeps(font_info const *fi, FILE *ofp) {
+    char *buf;
+    size_t len;
+
+    pf_getascii(fi->fontfile, 0, INT_MAX, &buf, &len);
+    fwrite(buf, 1, len, ofp);
+    sfree(buf);
+}
+
+static int hexval(char c) {
+    if (c >= '0' && c <= '9') return c - '0';
+    if (c >= 'A' && c <= 'F') return c - 'A' + 0xA;
+    if (c >= 'a' && c <= 'f') return c - 'a' + 0xa;
+    return 0;
+}
+
+static void pf_getbinary(t1_font *tf, size_t off, size_t len,
+			 char **bufp, size_t *lenp) {
+    t1_data *td = tf->data;
+    size_t blk, i;
+    int havenybble = 0;
+    char *p, nybble;
+
+    while (td && off >= td->length) {
+	off -= td->length;
+	td = td->next;
+    }
+    *bufp = NULL;
+    *lenp = 0;
+    while (td && len) {
+	blk = len < td->length ? len : td->length;
+	if (td->type == PFB_BINARY) {
+	    *bufp = sresize(*bufp, *lenp + blk, char);
+	    memcpy(*bufp + *lenp, td->data + off, blk);
+	    *lenp += blk;
+	} else {
+	    *bufp = sresize(*bufp, *lenp + blk / 2 + 1, char);
+	    p = *bufp + *lenp;
+	    for (i = 0; i < blk; i++) {
+		if (pf_isspace(td->data[off + i])) continue;
+		if (!havenybble)
+		    nybble = hexval(td->data[off+i]);
+		else
+		    *p++ = (nybble << 4) | hexval(td->data[off+i]);
+		havenybble = !havenybble;
+	    }
+	    *lenp = p - *bufp;
+	}
+	len -= blk;
+	td = td->next;
+	off = 0;
+    }   
+}
+
+
+/*
+ * Return the initial, unencrypted, part of a font.
+ */
+void pf_part1(font_info *fi, char **bufp, size_t *lenp) {
+    t1_font *tf = fi->fontfile;
+
+    if (tf->length1 == 0)
+	tf->length1 = pf_length1(tf);
+    pf_getascii(tf, 0, tf->length1, bufp, lenp);
+}
+
+/*
+ * Return the middle, encrypted, part of a font.
+ */
+void pf_part2(font_info *fi, char **bufp, size_t *lenp) {
+    t1_font *tf = fi->fontfile;
+
+    if (tf->length2 == 0)
+	tf->length2 = pf_length2(tf);
+    pf_getbinary(tf, tf->length1, tf->length2, bufp, lenp);
+    if (*lenp >= 256)
+	*lenp -= 256;
+}
+
+static char *pf_read_litstring(pfstate *pf) {
+    rdstringc rsc = { 0, 0, NULL };
+    int depth = 1;
+    int c;
+
+    rdaddc(&rsc, '(');
+    do {
+	c = pf_getc(pf);
+	switch (c) {
+	  case '(':
+	    depth++; break;
+	  case ')':
+	    depth--; break;
+	  case '\\':
+	    rdaddc(&rsc, '\\');
+	    c = pf_getc(pf);
+	    break;
+	}
+	if (c != EOF) rdaddc(&rsc, c);
+    } while (depth > 0 && c != EOF);
+    return rsc.text;
+}
+
+static char *pf_read_hexstring(pfstate *pf) {
+    rdstringc rsc = { 0, 0, NULL };
+    int c;
+
+    rdaddc(&rsc, '<');
+    do {
+	c = pf_getc(pf);
+	if (c != EOF) rdaddc(&rsc, c);
+    } while (c != '>' && c != EOF);
+    return rsc.text;
+}   
+
+static char *pf_read_word(pfstate *pf, int c) {
+    rdstringc rsc = { 0, 0, NULL };
+
+    rdaddc(&rsc, c);
+    if (c == '{' || c == '}' || c == '[' || c == ']')
+	return rsc.text;
+    for (;;) {
+	c = pf_getc(pf);
+	if (pf_isspecial(c) || pf_isspace(c) || c == EOF) break;
+	rdaddc(&rsc, c);
+    }
+    if (pf_isspecial(c)) pf_ungetc(c, pf);
+    return rsc.text;
+}   
+
+static char *pf_read_token(pfstate *pf) {
+    int c;
+
+    do {
+	c = pf_getc(pf);
+    } while (pf_isspace(c));
+    if (c == EOF) return NULL;
+    if (c == '%') {
+	do {
+	    c = pf_getc(pf);
+	} while (c != 012 && c != 015);
+	return pf_read_token(pf);
+    }
+    if (c == '(') return pf_read_litstring(pf);
+    if (c == '<') return pf_read_hexstring(pf);
+    return pf_read_word(pf, c);
+}