1 files changed, 331 insertions, 0 deletions
diff --git a/src/setproctitle.c b/src/setproctitle.c
new file mode 100644
index 0000000..0194023
--- /dev/null
+++ b/src/setproctitle.c
@@ -0,0 +1,331 @@
+/* ==========================================================================
+ * setproctitle.c - Linux/Darwin setproctitle.
+ * --------------------------------------------------------------------------
+ * Copyright (C) 2010  William Ahern
+ * Copyright (C) 2013  Salvatore Sanfilippo
+ * Copyright (C) 2013  Stam He
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to permit
+ * persons to whom the Software is furnished to do so, subject to the
+ * following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+ * NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ * ==========================================================================
+ */
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <stddef.h>	/* NULL size_t */
+#include <stdarg.h>	/* va_list va_start va_end */
+#include <stdlib.h>	/* malloc(3) setenv(3) clearenv(3) setproctitle(3) getprogname(3) */
+#include <stdio.h>	/* vsnprintf(3) snprintf(3) */
+
+#include <string.h>	/* strlen(3) strchr(3) strdup(3) memset(3) memcpy(3) */
+
+#include <errno.h>	/* errno program_invocation_name program_invocation_short_name */
+
+#if !defined(HAVE_SETPROCTITLE)
+#if (defined __NetBSD__ || defined __FreeBSD__ || defined __OpenBSD__ || defined __DragonFly__)
+#define HAVE_SETPROCTITLE 1
+#else
+#define HAVE_SETPROCTITLE 0
+#endif
+#endif
+
+
+#if !HAVE_SETPROCTITLE
+#if (defined __linux || defined __APPLE__)
+
+#ifdef __GLIBC__
+#define HAVE_CLEARENV
+#endif
+
+extern char **environ;
+
+static struct {
+	/* original value */
+	const char *arg0;
+
+	/* title space available */
+	char *base, *end;
+
+	 /* pointer to original nul character within base */
+	char *nul;
+
+	_Bool reset;
+	int error;
+} SPT;
+
+
+#ifndef SPT_MIN
+#define SPT_MIN(a, b) (((a) < (b))? (a) : (b))
+#endif
+
+static inline size_t spt_min(size_t a, size_t b) {
+	return SPT_MIN(a, b);
+} /* spt_min() */
+
+
+/*
+ * For discussion on the portability of the various methods, see
+ * http://lists.freebsd.org/pipermail/freebsd-stable/2008-June/043136.html
+ */
+int spt_clearenv(void) {
+#ifdef HAVE_CLEARENV
+	return clearenv();
+#else
+	extern char **environ;
+	static char **tmp;
+
+	if (!(tmp = malloc(sizeof *tmp)))
+		return errno;
+
+	tmp[0]  = NULL;
+	environ = tmp;
+
+	return 0;
+#endif
+} /* spt_clearenv() */
+
+
+static int spt_copyenv(int envc, char *oldenv[]) {
+	extern char **environ;
+	char **envcopy = NULL;
+	char *eq;
+	int i, error;
+	int envsize;
+
+	if (environ != oldenv)
+		return 0;
+
+	/* Copy environ into envcopy before clearing it. Shallow copy is
+	 * enough as clearenv() only clears the environ array.
+	 */
+	envsize = (envc + 1) * sizeof(char *);
+	envcopy = malloc(envsize);
+	if (!envcopy)
+		return ENOMEM;
+	memcpy(envcopy, oldenv, envsize);
+
+	/* Note that the state after clearenv() failure is undefined, but we'll
+	 * just assume an error means it was left unchanged.
+	 */
+	if ((error = spt_clearenv())) {
+		environ = oldenv;
+		free(envcopy);
+		return error;
+	}
+
+	/* Set environ from envcopy */
+	for (i = 0; envcopy[i]; i++) {
+		if (!(eq = strchr(envcopy[i], '=')))
+			continue;
+
+		*eq = '\0';
+		error = (0 != setenv(envcopy[i], eq + 1, 1))? errno : 0;
+		*eq = '=';
+
+		/* On error, do our best to restore state */
+		if (error) {
+#ifdef HAVE_CLEARENV
+			/* We don't assume it is safe to free environ, so we
+			 * may leak it. As clearenv() was shallow using envcopy
+			 * here is safe.
+			 */
+			environ = envcopy;
+#else
+			free(envcopy);
+			free(environ);  /* Safe to free, we have just alloc'd it */
+			environ = oldenv;
+#endif
+			return error;
+		}
+	}
+
+	free(envcopy);
+	return 0;
+} /* spt_copyenv() */
+
+
+static int spt_copyargs(int argc, char *argv[]) {
+	char *tmp;
+	int i;
+
+	for (i = 1; i < argc || (i >= argc && argv[i]); i++) {
+		if (!argv[i])
+			continue;
+
+		if (!(tmp = strdup(argv[i])))
+			return errno;
+
+		argv[i] = tmp;
+	}
+
+	return 0;
+} /* spt_copyargs() */
+
+/* Initialize and populate SPT to allow a future setproctitle()
+ * call.
+ *
+ * As setproctitle() basically needs to overwrite argv[0], we're
+ * trying to determine what is the largest contiguous block
+ * starting at argv[0] we can use for this purpose.
+ *
+ * As this range will overwrite some or all of the argv and environ
+ * strings, a deep copy of these two arrays is performed.
+ */
+void spt_init(int argc, char *argv[]) {
+        char **envp = environ;
+	char *base, *end, *nul, *tmp;
+	int i, error, envc;
+
+	if (!(base = argv[0]))
+		return;
+
+	/* We start with end pointing at the end of argv[0] */
+	nul = &base[strlen(base)];
+	end = nul + 1;
+
+	/* Attempt to extend end as far as we can, while making sure
+	 * that the range between base and end is only allocated to
+	 * argv, or anything that immediately follows argv (presumably
+	 * envp).
+	 */
+	for (i = 0; i < argc || (i >= argc && argv[i]); i++) {
+		if (!argv[i] || argv[i] < end)
+			continue;
+
+		if (end >= argv[i] && end <= argv[i] + strlen(argv[i]))
+			end = argv[i] + strlen(argv[i]) + 1;
+	}
+
+	/* In case the envp array was not an immediate extension to argv,
+	 * scan it explicitly.
+	 */
+	for (i = 0; envp[i]; i++) {
+		if (envp[i] < end)
+			continue;
+
+		if (end >= envp[i] && end <= envp[i] + strlen(envp[i]))
+			end = envp[i] + strlen(envp[i]) + 1;
+	}
+	envc = i;
+
+	/* We're going to deep copy argv[], but argv[0] will still point to
+	 * the old memory for the purpose of updating the title so we need
+	 * to keep the original value elsewhere.
+	 */
+	if (!(SPT.arg0 = strdup(argv[0])))
+		goto syerr;
+
+#if __linux__
+	if (!(tmp = strdup(program_invocation_name)))
+		goto syerr;
+
+	program_invocation_name = tmp;
+
+	if (!(tmp = strdup(program_invocation_short_name)))
+		goto syerr;
+
+	program_invocation_short_name = tmp;
+#elif __APPLE__
+	if (!(tmp = strdup(getprogname())))
+		goto syerr;
+
+	setprogname(tmp);
+#endif
+
+    /* Now make a full deep copy of the environment and argv[] */
+	if ((error = spt_copyenv(envc, envp)))
+		goto error;
+
+	if ((error = spt_copyargs(argc, argv)))
+		goto error;
+
+	SPT.nul  = nul;
+	SPT.base = base;
+	SPT.end  = end;
+
+	return;
+syerr:
+	error = errno;
+error:
+	SPT.error = error;
+} /* spt_init() */
+
+
+#ifndef SPT_MAXTITLE
+#define SPT_MAXTITLE 255
+#endif
+
+void setproctitle(const char *fmt, ...) {
+	char buf[SPT_MAXTITLE + 1]; /* use buffer in case argv[0] is passed */
+	va_list ap;
+	char *nul;
+	int len, error;
+
+	if (!SPT.base)
+		return;
+
+	if (fmt) {
+		va_start(ap, fmt);
+		len = vsnprintf(buf, sizeof buf, fmt, ap);
+		va_end(ap);
+	} else {
+		len = snprintf(buf, sizeof buf, "%s", SPT.arg0);
+	}
+
+	if (len <= 0)
+		{ error = errno; goto error; }
+
+	if (!SPT.reset) {
+		memset(SPT.base, 0, SPT.end - SPT.base);
+		SPT.reset = 1;
+	} else {
+		memset(SPT.base, 0, spt_min(sizeof buf, SPT.end - SPT.base));
+	}
+
+	len = spt_min(len, spt_min(sizeof buf, SPT.end - SPT.base) - 1);
+	memcpy(SPT.base, buf, len);
+	nul = &SPT.base[len];
+
+	if (nul < SPT.nul) {
+		*SPT.nul = '.';
+	} else if (nul == SPT.nul && &nul[1] < SPT.end) {
+		*SPT.nul = ' ';
+		*++nul = '\0';
+	}
+
+	return;
+error:
+	SPT.error = error;
+} /* setproctitle() */
+
+
+#endif /* __linux || __APPLE__ */
+#endif /* !HAVE_SETPROCTITLE */
+
+#ifdef SETPROCTITLE_TEST_MAIN
+int main(int argc, char *argv[]) {
+	spt_init(argc, argv);
+
+	printf("SPT.arg0: [%p] '%s'\n", SPT.arg0, SPT.arg0);
+	printf("SPT.base: [%p] '%s'\n", SPT.base, SPT.base);
+	printf("SPT.end: [%p] (%d bytes after base)'\n", SPT.end, (int) (SPT.end - SPT.base));
+	return 0;
+}
+#endif