# HG changeset patch
# User Francisco J Ballesteros <nemo.mbox@gmail.com>
# Date 1317230267 0
# Node ID 45c559389f50ee579a164a83fed9de51c7ed7b84
# Parent  86f0809cfdd50e38e4c7532fa2cc57cc399b1dd5
liberror: tiny error handling tools.
emalloc, erealloc, ...
they are found in so many programs
that they deserve to be in a library.

R=nix-dev, john
CC=nix-dev
http://codereview.appspot.com/5133046

diff -r 86f0809cfdd5 -r 45c559389f50 sys/include/error.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/include/error.h	Wed Sep 28 17:17:47 2011 +0000
@@ -0,0 +1,15 @@
+#pragma	lib	"liberror.a"
+#pragma src "/sys/src/liberror"
+
+typedef struct Channel Channel;
+
+#pragma incomplete Channel;
+
+#pragma varargck		argpos	esmprint 1
+
+char*	estrdup(char*);
+void*	emalloc(int);
+void*	emallocz(int, int);
+void*	erealloc(void*,int);
+char*	esmprint(char *fmt, ...);
+Channel*echancreate(int, int);
diff -r 86f0809cfdd5 -r 45c559389f50 sys/man/2/error
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/man/2/error	Wed Sep 28 17:17:47 2011 +0000
@@ -0,0 +1,48 @@
+.TH ERROR 2
+.SH NAME
+estrdup, emalloc, emallocz, erealloc, esmprint, echancreate \- error handling utilities
+.SH SYNOPSIS
+.B #include <u.h>
+.br
+.B #include <libc.h>
+.br
+.B #include <error.h>
+.PP
+.B
+char*	estrdup(char*)
+.br
+.B
+void*	emalloc(int);
+.br
+.B
+void*	emallocz(int, int);
+.br
+.B
+void*	erealloc(void*,int)
+.br
+.B
+void*	esmprint(char *fmt, ...)
+.br
+.B
+Channel*	echancreate(int, int)
+.br
+.SH DESCRIPTION
+These routiles are tools for error handling verions of memory allocation
+functions found elsewhere. 
+.PP
+Their are named like standard functions with the letter
+.B e
+prepended, and behave as expected for the
+standard function in each case. However, they check that the standard routine did its
+work and call
+.IR sysfatal (2)
+otherwise.
+All of them set the caller PC as the tag, using
+.IR setmalloctag (2).
+.PP
+.I Echancreate
+requires including the header for
+.I thread (2).
+Other ones do not.
+.SH SOURCE
+.B /sys/src/liberror
diff -r 86f0809cfdd5 -r 45c559389f50 sys/src/liberror/echancreate.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/src/liberror/echancreate.c	Wed Sep 28 17:17:47 2011 +0000
@@ -0,0 +1,15 @@
+#include <u.h>
+#include <libc.h>
+#include <error.h>
+#include <thread.h>
+
+Channel*
+echancreate(int sz, int n)
+{
+	Channel *c;
+
+	c = chancreate(sz, n);
+	if(c == nil)
+		sysfatal("chancreate: %r");
+	return c;
+}
diff -r 86f0809cfdd5 -r 45c559389f50 sys/src/liberror/emalloc.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/src/liberror/emalloc.c	Wed Sep 28 17:17:47 2011 +0000
@@ -0,0 +1,63 @@
+#include <u.h>
+#include <libc.h>
+#include <error.h>
+
+char*
+estrdup(char* s)
+{
+	s = strdup(s);
+	if(s == nil)
+		sysfatal("estrdup: not enough memory");
+	setmalloctag(s, getcallerpc(&s));
+	return s;
+}
+
+void*
+emalloc(int sz)
+{
+	void*	s;
+
+	s = mallocz(sz, 1);
+	if(s == nil)
+		sysfatal("emalloc: not enough memory");
+	setmalloctag(s, getcallerpc(&sz));
+	return s;
+}
+
+void*
+emallocz(int sz, int zero)
+{
+	void*	s;
+
+	s = mallocz(sz, zero);
+	if(s == nil)
+		sysfatal("emalloc: not enough memory");
+	setmalloctag(s, getcallerpc(&sz));
+	return s;
+}
+
+void*
+erealloc(void* p, int sz)
+{
+
+	p = realloc(p, sz);
+	if(p == nil)
+		sysfatal("erealloc: not enough memory");
+	setmalloctag(p, getcallerpc(&p));
+	return p;
+}
+
+char*
+esmprint(char *fmt, ...)
+{
+	va_list arg;
+	char *m;
+
+	va_start(arg, fmt);
+	m = vsmprint(fmt, arg);
+	va_end(arg);
+	if(m == nil)
+		sysfatal("smprint: %r");
+	setmalloctag(m, getcallerpc(&fmt));
+	return m;
+}
diff -r 86f0809cfdd5 -r 45c559389f50 sys/src/liberror/mkfile
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/src/liberror/mkfile	Wed Sep 28 17:17:47 2011 +0000
@@ -0,0 +1,16 @@
+</$objtype/mkfile
+
+LIB=/$objtype/lib/liberror.a
+OFILES=\
+	echancreate.$O\
+	emalloc.$O\
+
+HFILES=/sys/include/error.h
+
+UPDATE=\
+	mkfile\
+	$HFILES\
+	${OFILES:%.$O=%.c}\
+	${LIB:/$objtype/%=/386/%}\
+
+</sys/src/cmd/mksyslib