From: Ian Darwin <ian@darwinsys.com>
Date: Fri, 28 Aug 1987 20:29:07 +0000 (+0000)
Subject: Add Gilmore's getstr() and printstr().
X-Git-Tag: FILE3_27~429
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=d791c554e9398b2f1b25b96ef2059bdc19e998c4;p=file

Add Gilmore's getstr() and printstr().
Getstr() includes support for C escapes in strings.
---

diff --git a/src/apprentice.c b/src/apprentice.c
index 1fea372d..b9db6bf5 100644
--- a/src/apprentice.c
+++ b/src/apprentice.c
@@ -7,7 +7,8 @@
 #include "file.h"
 
 #define MAXSTR		500
-#define	EATAB {while (isascii(*l) && *l == '\t')  ++l;}
+#define	EATAB {while (isascii(*l) && isspace(*l))  ++l;}
+
 
 extern char *progname;
 extern char *magicfile;
@@ -17,6 +18,8 @@ extern long strtol();
 
 struct magic magic[MAXMAGIS];
 
+char *getstr();
+
 apprentice(fn)
 char *fn;
 {
@@ -55,12 +58,13 @@ char *l;
 int *ndx;
 {
 	int i = 0, nd = *ndx;
+	int slen;
 	static int warned = 0;
 	struct magic *m;
 
 	if (nd+1 >= MAXMAGIS){
 		if (warned++ == 0)
-			warning("magic tab overflow - increase MAXMAGIS beyond %d in file/apprentice.c\n", MAXMAGIS);
+			warning("magic table overflow - increase MAXMAGIS beyond %d in file/apprentice.c\n", MAXMAGIS);
 		return 0;
 	}
 	m = &magic[*ndx];
@@ -100,7 +104,7 @@ int *ndx;
 	}
 	EATAB;
 
-	if (*l == '>' || *l == '&' || *l == '=') {
+	if (*l == '>' || *l == '<' || *l == '&' || *l == '=') {
 		m->reln = *l;
 		++l;
 	} else
@@ -110,19 +114,23 @@ int *ndx;
 /* TODO finish this macro and start using it! */
 #define offsetcheck {if (offset > HOWMANY-1) warning("offset too big"); }
 	switch(m->type) {
+	/*
+	 * Do not remove the casts below.  They are vital.
+	 * When later compared with the data, the sign extension must
+	 * have happened.
+	 */
 	case BYTE:
-		m->value.l = strtol(l,&l,0);
+		m->value.l = (char) strtol(l,&l,0);
 		break;
 	case SHORT:
-		m->value.l = strtol(l,&l,0);
+		m->value.l = (short) strtol(l,&l,0);
 		break;
 	case LONG:
-		m->value.l = strtol(l,&l,0);
+		m->value.l = (long) strtol(l,&l,0);
 		break;
 	case STRING:
-		/* TODO check return from sscanf (system dependant?) */
-		(void) sscanf(l, "%[^\t]", m->value.s);
-		l += strlen(m->value.s);
+		l = getstr(l, m->value.s, sizeof(m->value.s), &slen);
+		m->vallen = slen;
 		break;
 	default:
 		warning("can't happen: m->type=%d\n", m->type);
@@ -142,3 +150,176 @@ int *ndx;
 	return 1;
 }
 
+/*
+ * Convert a string containing C character escapes.  Stop at an unescaped
+ * space or tab.
+ * Copy the converted version to "p", returning its length in *slen.
+ * Return updated scan pointer as function result.
+ */
+char *
+getstr(s, p, plen, slen)
+register char	*s;
+register char	*p;
+int	plen, *slen;
+{
+	char	*origs = s, *origp = p;
+	char	*pmax = p + plen - 1;
+	register char	c;
+	register int	val;
+
+	while((c = *s++) != '\0') {
+		if (isspace(c)) break;
+		if (p >= pmax) {
+			fprintf(stderr, "String too long: %s\n", origs);
+			break;
+		}
+		if(c == '\\') {
+			switch(c = *s++) {
+
+			case '\0':
+				goto out;
+
+			default:
+				*p++ = c;
+				break;
+
+			case 'n':
+				*p++ = '\n';
+				break;
+
+			case 'r':
+				*p++ = '\r';
+				break;
+
+			case 'b':
+				*p++ = '\b';
+				break;
+
+			case 't':
+				*p++ = '\t';
+				break;
+
+			case 'f':
+				*p++ = '\f';
+				break;
+
+			case 'v':
+				*p++ = '\v';
+				break;
+
+			/* \ and up to 3 octal digits */
+			case '0':
+			case '1':
+			case '2':
+			case '3':
+			case '4':
+			case '5':
+			case '6':
+			case '7':
+				val = c - '0';
+				c = *s++;  /* try for 2 */
+				if(c >= '0' && c <= '7') {
+					val = (val<<3) | (c - '0');
+					c = *s++;  /* try for 3 */
+					if(c >= '0' && c <= '7')
+						val = (val<<3) | (c-'0');
+					else
+						--s;
+				}
+				else
+					--s;
+				*p++ = val;
+				break;
+
+			/* \x and up to 3 hex digits */
+			case 'x':
+				val = 'x';	/* Default if no digits */
+				c = hextoint(*s++);	/* Get next char */
+				if (c >= 0) {
+					val = c;
+					c = hextoint(*s++);
+					if (c >= 0) {
+						val = (val << 4) + c;
+						c = hextoint(*s++);
+						if (c >= 0) {
+							val = (val << 4) + c;
+						} else
+							--s;
+					} else
+						--s;
+				} else
+					--s;
+				*p++ = val;
+				break;
+			}
+		} else
+			*p++ = c;
+	}
+out:
+	*p = '\0';
+	*slen = p - origp;
+	return(s);
+}
+
+
+/* Single hex char to int; -1 if not a hex char. */
+int
+hextoint(c)
+	char c;
+{
+	if (!isascii(c))	return -1;
+	if (isdigit(c))		return c - '0';
+	if ((c>='a')&(c<='f'))	return c + 10 - 'a';
+	if ((c>='A')&(c<='F'))	return c + 10 - 'A';
+				return -1;
+}
+
+
+/*
+ * Print a string containing C character escapes.
+ */
+void
+showstr(s)
+register char	*s;
+{
+	register char	c;
+
+	while((c = *s++) != '\0') {
+		if(c >= 040 && c <= 0176)
+			putchar(c);
+		else {
+			putchar('\\');
+			switch (c) {
+			
+			case '\n':
+				putchar('n');
+				break;
+
+			case '\r':
+				putchar('r');
+				break;
+
+			case '\b':
+				putchar('b');
+				break;
+
+			case '\t':
+				putchar('t');
+				break;
+
+			case '\f':
+				putchar('f');
+				break;
+
+			case '\v':
+				putchar('v');
+				break;
+
+			default:
+				printf("%.3o", c & 0377);
+				break;
+			}
+		}
+	}
+	putchar('\t');
+}