libkvm code janitoring

- make WARNS=6 clean for archs w/o strict alignment requirments
- add const, ANSIfy, remove unused vars, cast types for comparison
- thanks to differing definitions of VM_MIN_ADDRESS across our archs, we
  need to trick the compiler to not complain about signedness. We could
  either fix VM_MIN_ADDRESS to always be a simple integer or make the
  check conditional on $ARCH.

Closes PRs:	kern/42386, kern/83364
Reviewed by:	bde

1 files changed, 65 insertions, 92 deletions

diff --git a/lib/libkvm/kvm.c b/lib/libkvm/kvm.c
index b6d3bcd..cf29f10 100644
--- a/lib/libkvm/kvm.c
+++ b/lib/libkvm/kvm.c
@@ -77,8 +77,7 @@ static char sccsid[] = "@(#)kvm.c	8.2 (Berkeley) 2/13/94";
 int __fdnlist(int, struct nlist *);
 
 char *
-kvm_geterr(kd)
-	kvm_t *kd;
+kvm_geterr(kvm_t *kd)
 {
 	return (kd->errbuf);
 }
@@ -103,7 +102,7 @@ _kvm_err(kvm_t *kd, const char *program, const char *fmt, ...)
 		(void)fputc('\n', stderr);
 	} else
 		(void)vsnprintf(kd->errbuf,
-		    sizeof(kd->errbuf), (char *)fmt, ap);
+		    sizeof(kd->errbuf), fmt, ap);
 
 	va_end(ap);
 }
@@ -122,7 +121,7 @@ _kvm_syserr(kvm_t *kd, const char *program, const char *fmt, ...)
 	} else {
 		char *cp = kd->errbuf;
 
-		(void)vsnprintf(cp, sizeof(kd->errbuf), (char *)fmt, ap);
+		(void)vsnprintf(cp, sizeof(kd->errbuf), fmt, ap);
 		n = strlen(cp);
 		(void)snprintf(&cp[n], sizeof(kd->errbuf) - n, ": %s",
 		    strerror(errno));
@@ -131,25 +130,18 @@ _kvm_syserr(kvm_t *kd, const char *program, const char *fmt, ...)
 }
 
 void *
-_kvm_malloc(kd, n)
-	kvm_t *kd;
-	size_t n;
+_kvm_malloc(kvm_t *kd, size_t n)
 {
 	void *p;
 
 	if ((p = calloc(n, sizeof(char))) == NULL)
-		_kvm_err(kd, kd->program, "can't allocate %u bytes: %s",
+		_kvm_err(kd, kd->program, "can't allocate %zu bytes: %s",
 			 n, strerror(errno));
 	return (p);
 }
 
 static kvm_t *
-_kvm_open(kd, uf, mf, flag, errout)
-	kvm_t *kd;
-	const char *uf;
-	const char *mf;
-	int flag;
-	char *errout;
+_kvm_open(kvm_t *kd, const char *uf, const char *mf, int flag, char *errout)
 {
 	struct stat st;
 
@@ -242,12 +234,8 @@ failed:
 }
 
 kvm_t *
-kvm_openfiles(uf, mf, sf, flag, errout)
-	const char *uf;
-	const char *mf;
-	const char *sf __unused;
-	int flag;
-	char *errout;
+kvm_openfiles(const char *uf, const char *mf, const char *sf __unused, int flag,
+    char *errout)
 {
 	kvm_t *kd;
 
@@ -260,12 +248,8 @@ kvm_openfiles(uf, mf, sf, flag, errout)
 }
 
 kvm_t *
-kvm_open(uf, mf, sf, flag, errstr)
-	const char *uf;
-	const char *mf;
-	const char *sf __unused;
-	int flag;
-	const char *errstr;
+kvm_open(const char *uf, const char *mf, const char *sf __unused, int flag,
+    const char *errstr)
 {
 	kvm_t *kd;
 
@@ -280,8 +264,7 @@ kvm_open(uf, mf, sf, flag, errstr)
 }
 
 int
-kvm_close(kd)
-	kvm_t *kd;
+kvm_close(kvm_t *kd)
 {
 	int error = 0;
 
@@ -316,8 +299,9 @@ kvm_fdnlist_prefix(kvm_t *kd, struct nlist *nl, int missing, const char *prefix,
 {
 	struct nlist *n, *np, *p;
 	char *cp, *ce;
+	const char *ccp;
 	size_t len;
-	int unresolved;
+	int slen, unresolved;
 
 	/*
 	 * Calculate the space we need to malloc for nlist and names.
@@ -355,13 +339,13 @@ kvm_fdnlist_prefix(kvm_t *kd, struct nlist *nl, int missing, const char *prefix,
 			continue;
 		bcopy(p, np, sizeof(struct nlist));
 		/* Save the new\0orig. name so we can later match it again. */
-		len = snprintf(cp, ce - cp, "%s%s%c%s", prefix,
+		slen = snprintf(cp, ce - cp, "%s%s%c%s", prefix,
 		    (prefix[0] != '\0' && p->n_name[0] == '_') ?
 			(p->n_name + 1) : p->n_name, '\0', p->n_name);
-		if (len >= ce - cp)
+		if (slen < 0 || slen >= ce - cp)
 			continue;
 		np->n_name = cp;
-		cp += len + 1;
+		cp += slen + 1;
 		np++;
 		unresolved++;
 	}
@@ -385,8 +369,8 @@ kvm_fdnlist_prefix(kvm_t *kd, struct nlist *nl, int missing, const char *prefix,
 			if (p->n_type != N_UNDF)
 				continue;
 			/* Skip expanded name and compare to orig. one. */
-			cp = np->n_name + strlen(np->n_name) + 1;
-			if (strcmp(cp, p->n_name))
+			ccp = np->n_name + strlen(np->n_name) + 1;
+			if (strcmp(ccp, p->n_name) != 0)
 				continue;
 			/* Update nlist with new, translated results. */
 			p->n_type = np->n_type;
@@ -416,7 +400,8 @@ _kvm_nlist(kvm_t *kd, struct nlist *nl, int initialize)
 	int nvalid;
 	struct kld_sym_lookup lookup;
 	int error;
-	char *prefix = "", symname[1024]; /* XXX-BZ symbol name length limit? */
+	const char *prefix = "";
+	char symname[1024]; /* XXX-BZ symbol name length limit? */
 	int tried_vnet, tried_dpcpu;
 
 	/*
@@ -458,9 +443,8 @@ again:
 		error = snprintf(symname, sizeof(symname), "%s%s", prefix,
 		    (prefix[0] != '\0' && p->n_name[0] == '_') ?
 			(p->n_name + 1) : p->n_name);
-		if (error >= sizeof(symname))
+		if (error < 0 || error >= (int)sizeof(symname))
 			continue;
-
 		lookup.symname = symname;
 		if (lookup.symname[0] == '_')
 			lookup.symname++;
@@ -470,11 +454,11 @@ again:
 			p->n_other = 0;
 			p->n_desc = 0;
 			if (_kvm_vnet_initialized(kd, initialize) &&
-			    !strcmp(prefix, VNET_SYMPREFIX))
+			    !strcmp(prefix, VNET_SYMPREFIX) == 0)
 				p->n_value =
 				    _kvm_vnet_validaddr(kd, lookup.symvalue);
 			else if (_kvm_dpcpu_initialized(kd, initialize) &&
-			    !strcmp(prefix, DPCPU_SYMPREFIX))
+			    !strcmp(prefix, DPCPU_SYMPREFIX) == 0)
 				p->n_value =
 				    _kvm_dpcpu_validaddr(kd, lookup.symvalue);
 			else
@@ -511,9 +495,7 @@ again:
 }
 
 int
-kvm_nlist(kd, nl)
-	kvm_t *kd;
-	struct nlist *nl;
+kvm_nlist(kvm_t *kd, struct nlist *nl)
 {
 
 	/*
@@ -524,13 +506,11 @@ kvm_nlist(kd, nl)
 }
 
 ssize_t
-kvm_read(kd, kva, buf, len)
-	kvm_t *kd;
-	u_long kva;
-	void *buf;
-	size_t len;
+kvm_read(kvm_t *kd, u_long kva, void *buf, size_t len)
 {
 	int cc;
+	ssize_t cr;
+	off_t pa;
 	char *cp;
 
 	if (ISALIVE(kd)) {
@@ -540,59 +520,52 @@ kvm_read(kd, kva, buf, len)
 		 */
 		errno = 0;
 		if (lseek(kd->vmfd, (off_t)kva, 0) == -1 && errno != 0) {
-			_kvm_err(kd, 0, "invalid address (%x)", kva);
+			_kvm_err(kd, 0, "invalid address (%lx)", kva);
 			return (-1);
 		}
-		cc = read(kd->vmfd, buf, len);
-		if (cc < 0) {
+		cr = read(kd->vmfd, buf, len);
+		if (cr < 0) {
 			_kvm_syserr(kd, 0, "kvm_read");
 			return (-1);
-		} else if (cc < len)
+		} else if (cr < (ssize_t)len)
 			_kvm_err(kd, kd->program, "short read");
-		return (cc);
-	} else {
-		cp = buf;
-		while (len > 0) {
-			off_t pa;
-
-			cc = _kvm_kvatop(kd, kva, &pa);
-			if (cc == 0)
-				return (-1);
-			if (cc > len)
-				cc = len;
-			errno = 0;
-			if (lseek(kd->pmfd, pa, 0) == -1 && errno != 0) {
-				_kvm_syserr(kd, 0, _PATH_MEM);
-				break;
-			}
-			cc = read(kd->pmfd, cp, cc);
-			if (cc < 0) {
-				_kvm_syserr(kd, kd->program, "kvm_read");
-				break;
-			}
-			/*
-			 * If kvm_kvatop returns a bogus value or our core
-			 * file is truncated, we might wind up seeking beyond
-			 * the end of the core file in which case the read will
-			 * return 0 (EOF).
-			 */
-			if (cc == 0)
-				break;
-			cp += cc;
-			kva += cc;
-			len -= cc;
+		return (cr);
+	}
+
+	cp = buf;
+	while (len > 0) {
+		cc = _kvm_kvatop(kd, kva, &pa);
+		if (cc == 0)
+			return (-1);
+		if (cc > (ssize_t)len)
+			cc = len;
+		errno = 0;
+		if (lseek(kd->pmfd, pa, 0) == -1 && errno != 0) {
+			_kvm_syserr(kd, 0, _PATH_MEM);
+			break;
+		}
+		cr = read(kd->pmfd, cp, cc);
+		if (cr < 0) {
+			_kvm_syserr(kd, kd->program, "kvm_read");
+			break;
 		}
-		return (cp - (char *)buf);
+		/*
+		 * If kvm_kvatop returns a bogus value or our core file is
+		 * truncated, we might wind up seeking beyond the end of the
+		 * core file in which case the read will return 0 (EOF).
+		 */
+		if (cr == 0)
+			break;
+		cp += cr;
+		kva += cr;
+		len -= cr;
 	}
-	/* NOTREACHED */
+
+	return (cp - (char *)buf);
 }
 
 ssize_t
-kvm_write(kd, kva, buf, len)
-	kvm_t *kd;
-	u_long kva;
-	const void *buf;
-	size_t len;
+kvm_write(kvm_t *kd, u_long kva, const void *buf, size_t len)
 {
 	int cc;
 
@@ -602,14 +575,14 @@ kvm_write(kd, kva, buf, len)
 		 */
 		errno = 0;
 		if (lseek(kd->vmfd, (off_t)kva, 0) == -1 && errno != 0) {
-			_kvm_err(kd, 0, "invalid address (%x)", kva);
+			_kvm_err(kd, 0, "invalid address (%lx)", kva);
 			return (-1);
 		}
 		cc = write(kd->vmfd, buf, len);
 		if (cc < 0) {
 			_kvm_syserr(kd, 0, "kvm_write");
 			return (-1);
-		} else if (cc < len)
+		} else if ((size_t)cc < len)
 			_kvm_err(kd, kd->program, "short write");
 		return (cc);
 	} else {