This is fine with me, I think it was better without errno, but using it
can't do any harm. It is an extension TO set it, not to not set it, but
I am pretty sure it only happens on platforms I don't care about :-).
I suggest you check with djm or dtucker for ssh in case they do care, or
there are any other problem for portable.
On Sun, Nov 08, 2015 at 01:39:32AM +0100, Tobias Stoeckmann wrote:
> Here's an updated diff:
>
> - use "overflow" error message for snprintf and friends
> - use err instead of errx for out of memory conditions
> - if fatal() doesn't print error string, use ": %s", strerror(errno)
>
> Is this okay for ssh and tmux, which are out to be very portable?
> Nicholas mentioned that malloc is not required to set errno. I've also
> checked the standard and it's just an extension. Although at worst,
> the user sees a wrong error message...
>
> Index: usr.bin/cvs/xmalloc.c
> ===================================================================
> RCS file: /cvs/src/usr.bin/cvs/xmalloc.c,v
> retrieving revision 1.12
> diff -u -p -u -p -r1.12 xmalloc.c
> --- usr.bin/cvs/xmalloc.c 5 Nov 2015 09:48:21 -0000 1.12
> +++ usr.bin/cvs/xmalloc.c 8 Nov 2015 00:27:13 -0000
> @@ -13,6 +13,8 @@
> * called by a name other than "ssh" or "Secure Shell".
> */
>
> +#include <errno.h>
> +#include <limits.h>
> #include <stdint.h>
> #include <stdio.h>
> #include <stdlib.h>
> @@ -30,7 +32,8 @@ xmalloc(size_t size)
> fatal("xmalloc: zero size");
> ptr = malloc(size);
> if (ptr == NULL)
> - fatal("xmalloc: out of memory (allocating %lu bytes)", (u_long)
> size);
> + fatal("xmalloc: allocating %zu bytes: %s",
> + size, strerror(errno));
> return ptr;
> }
>
> @@ -41,12 +44,10 @@ xcalloc(size_t nmemb, size_t size)
>
> if (size == 0 || nmemb == 0)
> fatal("xcalloc: zero size");
> - if (SIZE_MAX / nmemb < size)
> - fatal("xcalloc: nmemb * size > SIZE_MAX");
> ptr = calloc(nmemb, size);
> if (ptr == NULL)
> - fatal("xcalloc: out of memory (allocating %lu bytes)",
> - (u_long)(size * nmemb));
> + fatal("xcalloc: allocating %zu * %zu bytes: %s",
> + nmemb, size, strerror(errno));
> return ptr;
> }
>
> @@ -54,28 +55,23 @@ void *
> xreallocarray(void *ptr, size_t nmemb, size_t size)
> {
> void *new_ptr;
> - size_t new_size = nmemb * size;
>
> - if (new_size == 0)
> - fatal("xrealloc: zero size");
> - if (SIZE_MAX / nmemb < size)
> - fatal("xrealloc: nmemb * size > SIZE_MAX");
> - new_ptr = realloc(ptr, new_size);
> + if (nmemb == 0 || size == 0)
> + fatal("xreallocarray: zero size");
> + new_ptr = reallocarray(ptr, nmemb, size);
> if (new_ptr == NULL)
> - fatal("xrealloc: out of memory (new_size %lu bytes)",
> - (u_long) new_size);
> + fatal("xreallocarray: allocating %zu * %zu bytes: %s",
> + nmemb, size, strerror(errno));
> return new_ptr;
> }
>
> char *
> xstrdup(const char *str)
> {
> - size_t len;
> char *cp;
>
> - len = strlen(str) + 1;
> - cp = xmalloc(len);
> - strlcpy(cp, str, len);
> + if ((cp = strdup(str)) == NULL)
> + fatal("xstrdup: %s", strerror(errno));
> return cp;
> }
>
> @@ -90,23 +86,26 @@ xasprintf(char **ret, const char *fmt, .
> va_end(ap);
>
> if (i < 0 || *ret == NULL)
> - fatal("xasprintf: could not allocate memory");
> + fatal("xasprintf: %s", strerror(errno));
>
> - return (i);
> + return i;
> }
>
> int
> -xsnprintf(char *str, size_t size, const char *fmt, ...)
> +xsnprintf(char *str, size_t len, const char *fmt, ...)
> {
> va_list ap;
> int i;
>
> + if (len > INT_MAX)
> + fatal("xsnprintf: len > INT_MAX");
> +
> va_start(ap, fmt);
> - i = vsnprintf(str, size, fmt, ap);
> + i = vsnprintf(str, len, fmt, ap);
> va_end(ap);
>
> - if (i == -1 || i >= (int)size)
> + if (i < 0 || i >= (int)len)
> fatal("xsnprintf: overflow");
>
> - return (i);
> + return i;
> }
> Index: usr.bin/diff/xmalloc.c
> ===================================================================
> RCS file: /cvs/src/usr.bin/diff/xmalloc.c,v
> retrieving revision 1.8
> diff -u -p -u -p -r1.8 xmalloc.c
> --- usr.bin/diff/xmalloc.c 25 Sep 2015 16:16:26 -0000 1.8
> +++ usr.bin/diff/xmalloc.c 8 Nov 2015 00:27:13 -0000
> @@ -27,9 +27,11 @@ xmalloc(size_t size)
> {
> void *ptr;
>
> + if (size == 0)
> + errx(2, "xmalloc: zero size");
> ptr = malloc(size);
> if (ptr == NULL)
> - err(2, "xmalloc %zu", size);
> + err(2, "xmalloc: allocating %zu bytes", size);
> return ptr;
> }
>
> @@ -40,8 +42,7 @@ xcalloc(size_t nmemb, size_t size)
>
> ptr = calloc(nmemb, size);
> if (ptr == NULL)
> - err(2, "xcalloc: out of memory (allocating %zu*%zu bytes)",
> - nmemb, size);
> + err(2, "xcalloc: allocating %zu * %zu bytes", nmemb, size);
> return ptr;
> }
>
> @@ -52,7 +53,8 @@ xreallocarray(void *ptr, size_t nmemb, s
>
> new_ptr = reallocarray(ptr, nmemb, size);
> if (new_ptr == NULL)
> - err(2, "xrealloc %zu*%zu", nmemb, size);
> + err(2, "xreallocarray: allocating %zu * %zu bytes",
> + nmemb, size);
> return new_ptr;
> }
>
> @@ -62,7 +64,7 @@ xstrdup(const char *str)
> char *cp;
>
> if ((cp = strdup(str)) == NULL)
> - err(1, "xstrdup");
> + err(2, "xstrdup");
> return cp;
> }
>
> @@ -79,5 +81,5 @@ xasprintf(char **ret, const char *fmt, .
> if (i < 0 || *ret == NULL)
> err(2, "xasprintf");
>
> - return (i);
> + return i;
> }
> Index: usr.bin/diff/xmalloc.h
> ===================================================================
> RCS file: /cvs/src/usr.bin/diff/xmalloc.h,v
> retrieving revision 1.3
> diff -u -p -u -p -r1.3 xmalloc.h
> --- usr.bin/diff/xmalloc.h 29 Apr 2015 04:00:25 -0000 1.3
> +++ usr.bin/diff/xmalloc.h 8 Nov 2015 00:27:13 -0000
> @@ -22,7 +22,6 @@
> void *xmalloc(size_t);
> void *xcalloc(size_t, size_t);
> void *xreallocarray(void *, size_t, size_t);
> -void xfree(void *);
> char *xstrdup(const char *);
> int xasprintf(char **, const char *, ...)
> __attribute__((__format__ (printf, 2, 3)))
> Index: usr.bin/file/xmalloc.c
> ===================================================================
> RCS file: /cvs/src/usr.bin/file/xmalloc.c,v
> retrieving revision 1.2
> diff -u -p -u -p -r1.2 xmalloc.c
> --- usr.bin/file/xmalloc.c 17 Jun 2015 18:51:11 -0000 1.2
> +++ usr.bin/file/xmalloc.c 8 Nov 2015 00:27:13 -0000
> @@ -31,9 +31,7 @@ xmalloc(size_t size)
> errx(1, "xmalloc: zero size");
> ptr = malloc(size);
> if (ptr == NULL)
> - errx(1,
> - "xmalloc: out of memory (allocating %zu bytes)",
> - size);
> + err(1, "xmalloc: allocating %zu bytes", size);
> return ptr;
> }
>
> @@ -44,12 +42,9 @@ xcalloc(size_t nmemb, size_t size)
>
> if (size == 0 || nmemb == 0)
> errx(1, "xcalloc: zero size");
> - if (SIZE_MAX / nmemb < size)
> - errx(1, "xcalloc: nmemb * size > SIZE_MAX");
> ptr = calloc(nmemb, size);
> if (ptr == NULL)
> - errx(1, "xcalloc: out of memory (allocating %zu bytes)",
> - (size * nmemb));
> + err(1, "xcalloc: allocating %zu * %zu bytes", nmemb, size);
> return ptr;
> }
>
> @@ -60,8 +55,8 @@ xreallocarray(void *ptr, size_t nmemb, s
>
> new_ptr = reallocarray(ptr, nmemb, size);
> if (new_ptr == NULL)
> - errx(1, "xreallocarray: out of memory (new_size %zu bytes)",
> - nmemb * size);
> + err(1, "xreallocarray: allocating %zu * %zu bytes",
> + nmemb, size);
> return new_ptr;
> }
>
> @@ -86,7 +81,7 @@ xasprintf(char **ret, const char *fmt, .
> va_end(ap);
>
> if (i < 0 || *ret == NULL)
> - errx(1, "xasprintf: could not allocate memory");
> + err(1, "xasprintf");
>
> - return (i);
> + return i;
> }
> Index: usr.bin/file/xmalloc.h
> ===================================================================
> RCS file: /cvs/src/usr.bin/file/xmalloc.h,v
> retrieving revision 1.2
> diff -u -p -u -p -r1.2 xmalloc.h
> --- usr.bin/file/xmalloc.h 20 Jul 2015 08:51:41 -0000 1.2
> +++ usr.bin/file/xmalloc.h 8 Nov 2015 00:27:13 -0000
> @@ -27,4 +27,4 @@ int xasprintf(char **, const char *, ..
> __attribute__((__format__ (printf, 2, 3)))
> __attribute__((__nonnull__ (2)));
>
> -#endif /* XMALLOC_H */
> +#endif /* XMALLOC_H */
> Index: usr.bin/rcs/xmalloc.c
> ===================================================================
> RCS file: /cvs/src/usr.bin/rcs/xmalloc.c,v
> retrieving revision 1.10
> diff -u -p -u -p -r1.10 xmalloc.c
> --- usr.bin/rcs/xmalloc.c 17 Jun 2015 20:50:10 -0000 1.10
> +++ usr.bin/rcs/xmalloc.c 8 Nov 2015 00:27:13 -0000
> @@ -31,9 +31,7 @@ xmalloc(size_t size)
> errx(1, "xmalloc: zero size");
> ptr = malloc(size);
> if (ptr == NULL)
> - errx(1,
> - "xmalloc: out of memory (allocating %zu bytes)",
> - size);
> + err(1, "xmalloc: allocating %zu bytes", size);
> return ptr;
> }
>
> @@ -44,12 +42,9 @@ xcalloc(size_t nmemb, size_t size)
>
> if (size == 0 || nmemb == 0)
> errx(1, "xcalloc: zero size");
> - if (SIZE_MAX / nmemb < size)
> - errx(1, "xcalloc: nmemb * size > SIZE_MAX");
> ptr = calloc(nmemb, size);
> if (ptr == NULL)
> - errx(1, "xcalloc: out of memory (allocating %zu bytes)",
> - (size * nmemb));
> + err(1, "xcalloc: allocating %zu * %zu bytes", nmemb, size);
> return ptr;
> }
>
> @@ -60,8 +55,8 @@ xreallocarray(void *ptr, size_t nmemb, s
>
> new_ptr = reallocarray(ptr, nmemb, size);
> if (new_ptr == NULL)
> - errx(1, "xreallocarray: out of memory (new_size %zu bytes)",
> - nmemb * size);
> + err(1, "xreallocarray: allocating %zu * %zu bytes",
> + nmemb, size);
> return new_ptr;
> }
>
> @@ -86,7 +81,7 @@ xasprintf(char **ret, const char *fmt, .
> va_end(ap);
>
> if (i < 0 || *ret == NULL)
> - errx(1, "xasprintf: could not allocate memory");
> + err(1, "xasprintf");
>
> - return (i);
> + return i;
> }
> Index: usr.bin/rcs/xmalloc.h
> ===================================================================
> RCS file: /cvs/src/usr.bin/rcs/xmalloc.h,v
> retrieving revision 1.3
> diff -u -p -u -p -r1.3 xmalloc.h
> --- usr.bin/rcs/xmalloc.h 13 Jun 2015 20:15:21 -0000 1.3
> +++ usr.bin/rcs/xmalloc.h 8 Nov 2015 00:27:13 -0000
> @@ -27,4 +27,4 @@ int xasprintf(char **, const char *, ..
> __attribute__((__format__ (printf, 2, 3)))
> __attribute__((__nonnull__ (2)));
>
> -#endif /* XMALLOC_H */
> +#endif /* XMALLOC_H */
> Index: usr.bin/ssh/xmalloc.c
> ===================================================================
> RCS file: /cvs/src/usr.bin/ssh/xmalloc.c,v
> retrieving revision 1.32
> diff -u -p -u -p -r1.32 xmalloc.c
> --- usr.bin/ssh/xmalloc.c 24 Apr 2015 01:36:01 -0000 1.32
> +++ usr.bin/ssh/xmalloc.c 8 Nov 2015 00:27:14 -0000
> @@ -13,6 +13,7 @@
> * called by a name other than "ssh" or "Secure Shell".
> */
>
> +#include <errno.h>
> #include <stdarg.h>
> #include <stdint.h>
> #include <stdio.h>
> @@ -31,7 +32,8 @@ xmalloc(size_t size)
> fatal("xmalloc: zero size");
> ptr = malloc(size);
> if (ptr == NULL)
> - fatal("xmalloc: out of memory (allocating %zu bytes)", size);
> + fatal("xmalloc: allocating %zu bytes: %s", size,
> + strerror(errno));
> return ptr;
> }
>
> @@ -42,12 +44,10 @@ xcalloc(size_t nmemb, size_t size)
>
> if (size == 0 || nmemb == 0)
> fatal("xcalloc: zero size");
> - if (SIZE_MAX / nmemb < size)
> - fatal("xcalloc: nmemb * size > SIZE_MAX");
> ptr = calloc(nmemb, size);
> if (ptr == NULL)
> - fatal("xcalloc: out of memory (allocating %zu bytes)",
> - size * nmemb);
> + fatal("xcalloc: allocating %zu * %zu bytes: %s",
> + nmemb, size, strerror(errno));
> return ptr;
> }
>
> @@ -58,20 +58,18 @@ xreallocarray(void *ptr, size_t nmemb, s
>
> new_ptr = reallocarray(ptr, nmemb, size);
> if (new_ptr == NULL)
> - fatal("xreallocarray: out of memory (%zu elements of %zu
> bytes)",
> - nmemb, size);
> + fatal("xreallocarray: allocating %zu * %zu bytes: %s",
> + nmemb, size, strerror(errno));
> return new_ptr;
> }
>
> char *
> xstrdup(const char *str)
> {
> - size_t len;
> char *cp;
>
> - len = strlen(str) + 1;
> - cp = xmalloc(len);
> - strlcpy(cp, str, len);
> + if ((cp = strdup(str)) == NULL)
> + fatal("xstrdup: %s", strerror(errno));
> return cp;
> }
>
> @@ -86,7 +84,7 @@ xasprintf(char **ret, const char *fmt, .
> va_end(ap);
>
> if (i < 0 || *ret == NULL)
> - fatal("xasprintf: could not allocate memory");
> + fatal("xasprintf: %s", strerror(errno));
>
> - return (i);
> + return i;
> }
> Index: usr.bin/ssh/xmalloc.h
> ===================================================================
> RCS file: /cvs/src/usr.bin/ssh/xmalloc.h,v
> retrieving revision 1.15
> diff -u -p -u -p -r1.15 xmalloc.h
> --- usr.bin/ssh/xmalloc.h 24 Apr 2015 01:36:01 -0000 1.15
> +++ usr.bin/ssh/xmalloc.h 8 Nov 2015 00:27:14 -0000
> @@ -16,6 +16,9 @@
> * called by a name other than "ssh" or "Secure Shell".
> */
>
> +#ifndef XMALLOC_H
> +#define XMALLOC_H
> +
> void *xmalloc(size_t);
> void *xcalloc(size_t, size_t);
> void *xreallocarray(void *, size_t, size_t);
> @@ -23,3 +26,5 @@ char *xstrdup(const char *);
> int xasprintf(char **, const char *, ...)
> __attribute__((__format__ (printf, 2, 3)))
> __attribute__((__nonnull__ (2)));
> +
> +#endif /* XMALLOC_H */
> Index: usr.bin/tmux/xmalloc.c
> ===================================================================
> RCS file: /cvs/src/usr.bin/tmux/xmalloc.c,v
> retrieving revision 1.7
> diff -u -p -u -p -r1.7 xmalloc.c
> --- usr.bin/tmux/xmalloc.c 20 Oct 2014 23:57:14 -0000 1.7
> +++ usr.bin/tmux/xmalloc.c 8 Nov 2015 00:27:14 -0000
> @@ -25,16 +25,13 @@
> #include "tmux.h"
>
> char *
> -xstrdup(const char *s)
> +xstrdup(const char *str)
> {
> - char *ptr;
> - size_t len;
> + char *cp;
>
> - len = strlen(s) + 1;
> - ptr = xmalloc(len);
> -
> - strlcpy(ptr, s, len);
> - return (ptr);
> + if ((cp = strdup(str)) == NULL)
> + fatal("xstrdup");
> + return (cp);
> }
>
> void *
> @@ -43,11 +40,9 @@ xcalloc(size_t nmemb, size_t size)
> void *ptr;
>
> if (size == 0 || nmemb == 0)
> - fatalx("zero size");
> - if (SIZE_MAX / nmemb < size)
> - fatalx("nmemb * size > SIZE_MAX");
> + fatalx("xcalloc: zero size");
> if ((ptr = calloc(nmemb, size)) == NULL)
> - fatal("xcalloc failed");
> + log_fatal("xcalloc: allocating %zu bytes", size);
>
> return (ptr);
> }
> @@ -58,9 +53,9 @@ xmalloc(size_t size)
> void *ptr;
>
> if (size == 0)
> - fatalx("zero size");
> + fatalx("xmalloc: zero size");
> if ((ptr = malloc(size)) == NULL)
> - fatal("xmalloc failed");
> + log_fatal("xmalloc: allocating %zu bytes", size);
>
> return (ptr);
> }
> @@ -71,9 +66,9 @@ xrealloc(void *oldptr, size_t newsize)
> void *newptr;
>
> if (newsize == 0)
> - fatalx("zero size");
> + fatalx("xrealloc: zero size");
> if ((newptr = realloc(oldptr, newsize)) == NULL)
> - fatal("xrealloc failed");
> + log_fatal("xrealloc: allocating %zu bytes", newsize);
>
> return (newptr);
> }
> @@ -81,15 +76,13 @@ xrealloc(void *oldptr, size_t newsize)
> void *
> xreallocarray(void *oldptr, size_t nmemb, size_t size)
> {
> - size_t newsize = nmemb * size;
> void *newptr;
>
> - if (newsize == 0)
> - fatalx("zero size");
> - if (SIZE_MAX / nmemb < size)
> - fatalx("nmemb * size > SIZE_MAX");
> - if ((newptr = realloc(oldptr, newsize)) == NULL)
> - fatal("xreallocarray failed");
> + if (nmemb == 0 || size == 0)
> + fatalx("xreallocarray: zero size");
> + if ((newptr = reallocarray(oldptr, nmemb, size)) == NULL)
> + log_fatal("xreallocarray: allocating %zu * %zu bytes",
> + nmemb, size);
>
> return (newptr);
> }
> @@ -114,7 +107,7 @@ xvasprintf(char **ret, const char *fmt,
>
> i = vasprintf(ret, fmt, ap);
> if (i < 0 || *ret == NULL)
> - fatal("xvasprintf failed");
> + fatal("xvasprintf");
>
> return (i);
> }
> @@ -138,11 +131,11 @@ xvsnprintf(char *buf, size_t len, const
> int i;
>
> if (len > INT_MAX)
> - fatalx("len > INT_MAX");
> + fatalx("xvsnprintf: len > INT_MAX");
>
> i = vsnprintf(buf, len, fmt, ap);
> - if (i < 0)
> - fatal("vsnprintf failed");
> + if (i < 0 || i >= (int)len)
> + fatalx("xvsnprintf: overflow");
>
> return (i);
> }
