diff options
Diffstat (limited to 'lib/libc/gen/setproctitle.c')
| -rw-r--r-- | lib/libc/gen/setproctitle.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/lib/libc/gen/setproctitle.c b/lib/libc/gen/setproctitle.c new file mode 100644 index 000000000000..715951a8c96d --- /dev/null +++ b/lib/libc/gen/setproctitle.c @@ -0,0 +1,218 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 1995 Peter Wemm + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "namespace.h" +#include <sys/param.h> +#include <sys/elf_common.h> +#include <sys/exec.h> +#include <sys/sysctl.h> + +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include "un-namespace.h" + +#include "libc_private.h" + +/* + * Older FreeBSD 2.0, 2.1 and 2.2 had different ps_strings structures and + * in different locations. + * 1: old_ps_strings at the very top of the stack. + * 2: old_ps_strings at SPARE_USRSPACE below the top of the stack. + * 3: ps_strings at the very top of the stack. + * We only support a kernel providing #3 style ps_strings. + * + * For historical purposes, a definition of the old ps_strings structure + * and location is preserved below: +struct old_ps_strings { + char *old_ps_argvstr; + int old_ps_nargvstr; + char *old_ps_envstr; + int old_ps_nenvstr; +}; +#define OLD_PS_STRINGS ((struct old_ps_strings *) \ + (USRSTACK - SPARE_USRSPACE - sizeof(struct old_ps_strings))) + */ + +#include <stdarg.h> + +#define SPT_BUFSIZE 2048 /* from other parts of sendmail */ + +static char * +setproctitle_internal(const char *fmt, va_list ap) +{ + static struct ps_strings *ps_strings; + static char *buf = NULL; + static char *obuf = NULL; + static char **oargv; + static int oargc = -1; + static char *nargv[2] = { NULL, NULL }; + char **nargvp; + int nargc; + int i; + size_t len; + unsigned long ul_ps_strings; + + if (buf == NULL) { + buf = malloc(SPT_BUFSIZE); + if (buf == NULL) + return (NULL); + nargv[0] = buf; + } + + if (obuf == NULL ) { + obuf = malloc(SPT_BUFSIZE); + if (obuf == NULL) + return (NULL); + *obuf = '\0'; + } + + if (fmt) { + buf[SPT_BUFSIZE - 1] = '\0'; + + if (fmt[0] == '-') { + /* skip program name prefix */ + fmt++; + len = 0; + } else { + /* print program name heading for grep */ + (void)snprintf(buf, SPT_BUFSIZE, "%s: ", _getprogname()); + len = strlen(buf); + } + + /* print the argument string */ + (void)vsnprintf(buf + len, SPT_BUFSIZE - len, fmt, ap); + + nargvp = nargv; + nargc = 1; + } else if (*obuf != '\0') { + /* Idea from NetBSD - reset the title on fmt == NULL */ + nargvp = oargv; + nargc = oargc; + } else + /* Nothing to restore */ + return (NULL); + + if (ps_strings == NULL) + (void)_elf_aux_info(AT_PS_STRINGS, &ps_strings, + sizeof(ps_strings)); + + if (ps_strings == NULL) { + len = sizeof(ul_ps_strings); + if (sysctlbyname("kern.ps_strings", &ul_ps_strings, &len, NULL, + 0) == -1) + return (NULL); + ps_strings = (struct ps_strings *)ul_ps_strings; + } + + if (ps_strings == NULL) + return (NULL); + + /* + * PS_STRINGS points to zeroed memory on a style #2 kernel. + * Should not happen. + */ + if (ps_strings->ps_argvstr == NULL) + return (NULL); + + /* style #3 */ + if (oargc == -1) { + /* Record our original args */ + oargc = ps_strings->ps_nargvstr; + oargv = ps_strings->ps_argvstr; + for (i = len = 0; i < oargc; i++) { + /* + * The program may have scribbled into its + * argv array, e.g., to remove some arguments. + * If that has happened, break out before + * trying to call strlen on a NULL pointer. + */ + if (oargv[i] == NULL) { + oargc = i; + break; + } + snprintf(obuf + len, SPT_BUFSIZE - len, "%s%s", + len != 0 ? " " : "", oargv[i]); + if (len != 0) + len++; + len += strlen(oargv[i]); + if (len >= SPT_BUFSIZE) + break; + } + } + ps_strings->ps_nargvstr = nargc; + ps_strings->ps_argvstr = nargvp; + + return (nargvp[0]); +} + +static int fast_update = 0; + +void +setproctitle_fast(const char *fmt, ...) +{ + va_list ap; + char *buf; + int oid[4]; + + va_start(ap, fmt); + buf = setproctitle_internal(fmt, ap); + va_end(ap); + + if (buf && !fast_update) { + /* Tell the kernel to start looking in user-space */ + oid[0] = CTL_KERN; + oid[1] = KERN_PROC; + oid[2] = KERN_PROC_ARGS; + oid[3] = -1; + sysctl(oid, 4, 0, 0, "", 0); + fast_update = 1; + } +} + +void +setproctitle(const char *fmt, ...) +{ + va_list ap; + char *buf; + int oid[4]; + + va_start(ap, fmt); + buf = setproctitle_internal(fmt, ap); + va_end(ap); + + if (buf != NULL) { + /* Set the title into the kernel cached command line */ + oid[0] = CTL_KERN; + oid[1] = KERN_PROC; + oid[2] = KERN_PROC_ARGS; + oid[3] = -1; + sysctl(oid, 4, 0, 0, buf, strlen(buf) + 1); + fast_update = 0; + } +} |