Adding upstream version 3.5.24.upstream/3.5.24upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 177 insertions, 0 deletions

diff --git a/src/qmgr/qmgr_feedback.c b/src/qmgr/qmgr_feedback.c
new file mode 100644
index 0000000..bf7aebb
--- /dev/null
+++ b/src/qmgr/qmgr_feedback.c
@@ -0,0 +1,177 @@
+/*++
+/* NAME
+/*	qmgr_feedback 3
+/* SUMMARY
+/*	delivery agent feedback management
+/* SYNOPSIS
+/*	#include "qmgr.h"
+/*
+/*	void	qmgr_feedback_init(fbck_ctl, name_prefix, name_tail,
+/*					def_name, def_value)
+/*	QMGR_FEEDBACK *fbck_ctl;
+/*	const char *name_prefix;
+/*	const char *name_tail;
+/*	const char *def_name;
+/*	const char *def_value;
+/*
+/*	double	QMGR_FEEDBACK_VAL(fbck_ctl, concurrency)
+/*	QMGR_FEEDBACK *fbck_ctl;
+/*	const int concurrency;
+/* DESCRIPTION
+/*	Upon completion of a delivery request, a delivery agent
+/*	provides a hint that the scheduler should dedicate fewer or
+/*	more resources to a specific destination.
+/*
+/*	qmgr_feedback_init() looks up transport-dependent positive
+/*	or negative concurrency feedback control information from
+/*	main.cf, and converts it to internal form.
+/*
+/*	QMGR_FEEDBACK_VAL() computes a concurrency adjustment based
+/*	on a preprocessed feedback control information and the
+/*	current concurrency window. This is an "unsafe" macro that
+/*	evaluates some arguments multiple times.
+/*
+/*	Arguments:
+/* .IP fbck_ctl
+/*	Pointer to QMGR_FEEDBACK structure where the result will
+/*	be stored.
+/* .IP name_prefix
+/*	Mail delivery transport name, used as the initial portion
+/*	of a transport-dependent concurrency feedback parameter
+/*	name.
+/* .IP name_tail
+/*	The second, and fixed, portion of a transport-dependent
+/*	concurrency feedback parameter.
+/* .IP def_name
+/*	The name of a default feedback parameter.
+/* .IP def_val
+/*	The value of the default feedback parameter.
+/* .IP concurrency
+/*	Delivery concurrency for concurrency-dependent feedback calculation.
+/* DIAGNOSTICS
+/*	Warning: configuration error or unreasonable input. The program
+/*	uses name_tail feedback instead.
+/*	Panic: consistency check failure.
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <stdlib.h>
+#include <limits.h>			/* INT_MAX */
+#include <stdio.h>			/* sscanf() */
+#include <string.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <name_code.h>
+#include <stringops.h>
+#include <mymalloc.h>
+
+/* Global library. */
+
+#include <mail_params.h>
+#include <mail_conf.h>
+
+/* Application-specific. */
+
+#include "qmgr.h"
+
+ /*
+  * Lookup tables for main.cf feedback method names.
+  */
+const NAME_CODE qmgr_feedback_map[] = {
+    CONC_FDBACK_NAME_WIN, QMGR_FEEDBACK_IDX_WIN,
+#ifdef QMGR_FEEDBACK_IDX_SQRT_WIN
+    CONC_FDBACK_NAME_SQRT_WIN, QMGR_FEEDBACK_IDX_SQRT_WIN,
+#endif
+    0, QMGR_FEEDBACK_IDX_NONE,
+};
+
+/* qmgr_feedback_init - initialize feedback control */
+
+void    qmgr_feedback_init(QMGR_FEEDBACK *fb,
+			           const char *name_prefix,
+			           const char *name_tail,
+			           const char *def_name,
+			           const char *def_val)
+{
+    double  enum_val;
+    char    denom_str[30 + 1];
+    double  denom_val;
+    char    slash[1 + 1];
+    char    junk;
+    char   *fbck_name;
+    char   *fbck_val;
+
+    /*
+     * Look up the transport-dependent feedback value.
+     */
+    fbck_name = concatenate(name_prefix, name_tail, (char *) 0);
+    fbck_val = get_mail_conf_str(fbck_name, def_val, 1, 0);
+
+    /*
+     * We allow users to express feedback as 1/8, as a more user-friendly
+     * alternative to 0.125 (or worse, having users specify the number of
+     * events in a feedback hysteresis cycle).
+     * 
+     * We use some sscanf() fu to parse the value into numerator and optional
+     * "/" followed by denominator. We're doing this only a few times during
+     * the process life time, so we strive for convenience instead of speed.
+     */
+#define INCLUSIVE_BOUNDS(val, low, high) ((val) >= (low) && (val) <= (high))
+
+    fb->hysteresis = 1;				/* legacy */
+    fb->base = -1;				/* assume error */
+
+    switch (sscanf(fbck_val, "%lf %1[/] %30s%c",
+		   &enum_val, slash, denom_str, &junk)) {
+    case 1:
+	fb->index = QMGR_FEEDBACK_IDX_NONE;
+	fb->base = enum_val;
+	break;
+    case 3:
+	if ((fb->index = name_code(qmgr_feedback_map, NAME_CODE_FLAG_NONE,
+				   denom_str)) != QMGR_FEEDBACK_IDX_NONE) {
+	    fb->base = enum_val;
+	} else if (INCLUSIVE_BOUNDS(enum_val, 0, INT_MAX)
+		   && sscanf(denom_str, "%lf%c", &denom_val, &junk) == 1
+		   && INCLUSIVE_BOUNDS(denom_val, 1.0 / INT_MAX, INT_MAX)) {
+	    fb->base = enum_val / denom_val;
+	}
+	break;
+    }
+
+    /*
+     * Sanity check. If input is bad, we just warn and use a reasonable
+     * default.
+     */
+    if (!INCLUSIVE_BOUNDS(fb->base, 0, 1)) {
+	msg_warn("%s: ignoring malformed or unreasonable feedback: %s",
+		 strcmp(fbck_val, def_val) ? fbck_name : def_name, fbck_val);
+	fb->index = QMGR_FEEDBACK_IDX_NONE;
+	fb->base = 1;
+    }
+
+    /*
+     * Performance debugging/analysis.
+     */
+    if (var_conc_feedback_debug)
+	msg_info("%s: %s feedback type %d value at %d: %g",
+		 name_prefix, strcmp(fbck_val, def_val) ?
+		 fbck_name : def_name, fb->index, var_init_dest_concurrency,
+		 QMGR_FEEDBACK_VAL(*fb, var_init_dest_concurrency));
+
+    myfree(fbck_name);
+    myfree(fbck_val);
+}