From e204830545e686dc6a0ec04de9922f9c717a5ce2 Mon Sep 17 00:00:00 2001
From: mar <mar>
Date: Thu, 19 Aug 1993 15:05:22 +0000
Subject: [PATCH] detect deadlock errors

---
 regtape/students.dc | 62 +++++++++++++++++++++++++++++++++++++--------
 1 file changed, 51 insertions(+), 11 deletions(-)

diff --git a/regtape/students.dc b/regtape/students.dc
index d0a69cad..80462c78 100644
--- a/regtape/students.dc
+++ b/regtape/students.dc
@@ -77,8 +77,9 @@ struct entry {
 char *whoami;
 int newfinger = 0;
 
-#define sqlfail() (sqlca.sqlcode && sqlca.sqlcode != 100)
 #define SQL_DUPLICATE -40100
+#define SQL_DEADLOCK -49900
+#define sqlfail() (sqlca.sqlcode && sqlca.sqlcode != 100)
 
 main(argc, argv)
 int argc;
@@ -124,11 +125,17 @@ char **argv;
     }
 
     while (e = get_next_entry(in)) {
+    again:
 	process_entry(e);
 	EXEC SQL COMMIT WORK;
 	if (sqlca.sqlcode != 0) {
-	    com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
-	    exit(1);
+	    if (sqlca.sqlcode == SQL_DEADLOCK) {
+		com_err(whoami, MR_DEADLOCK, "commiting work");
+		goto again;
+	    } else {
+		com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
+		exit(1);
+	    }
 	}
 	if (wait) {
 	    printf("Next");
@@ -277,6 +284,10 @@ struct entry *e;
 	if (sqlca.sqlcode == SQL_DUPLICATE) {
 	    com_err(whoami, 0, "duplicate ID number %s on user %s %s", sid, first, last);
 	    return;
+	} else if (sqlca.sqlcode == SQL_DEADLOCK) {
+	    com_err(whoami, MR_DEADLOCK, "looking up user %s", sid);
+	    EXEC SQL ROLLBACK;
+	    return process_entry(e);
 	} else
 	  sqlexit();
     }
@@ -285,7 +296,14 @@ struct entry *e;
 	  INTO :id, :dfirst, :dlast, :dmiddle, :class, :haddr, :hphone, :ophone, :status, :dept
 	  FROM users
 	  WHERE last = :last and first = :first and clearid = :eid;
-	if (sqlfail() && sqlca.sqlcode != SQL_DUPLICATE) sqlexit();
+	if (sqlfail()) {
+	    if (sqlca.sqlcode == SQL_DEADLOCK) {
+		com_err(whoami, MR_DEADLOCK, "looking up user %s", sid);
+		EXEC SQL ROLLBACK;
+		return process_entry(e);
+	    } else if (sqlca.sqlcode != SQL_DUPLICATE)
+	      sqlexit();
+	}
 	encrypted++;
 	if (id == 0) {
 	    newuser(e);
@@ -458,8 +476,14 @@ struct entry *e;
 	    xmodtime = date('now'), clearid = :sid
 	  WHERE users_id = :id;
 	if (sqlca.sqlcode != 0) {
-	    com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
-	    exit(1);
+	    if (sqlca.sqlcode == SQL_DEADLOCK) {
+		com_err(whoami, MR_DEADLOCK, "updating user %s", sid);
+		EXEC SQL ROLLBACK;
+		return process_entry(e);
+	    } else {
+		com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
+		exit(1);
+	    }
 	}
     }  else {
 	EXEC SQL REPEATED UPDATE users
@@ -468,8 +492,14 @@ struct entry *e;
 	    xmodtime = date('now'), clearid = :sid
 	  WHERE users_id = :id;
 	if (sqlca.sqlcode != 0) {
-	    com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
-	    exit(1);
+	    if (sqlca.sqlcode == SQL_DEADLOCK) {
+		com_err(whoami, MR_DEADLOCK, "updating user %s", sid);
+		EXEC SQL ROLLBACK;
+		return process_entry(e);
+	    } else {
+		com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
+		exit(1);
+	    }
 	}
     }
 }
@@ -570,8 +600,14 @@ struct entry *e;
 	      :ophone, :dept, 'now', :who, :prog, 'NONE', :name, :dept,
 	      :title, :raddr, :hphone, :ophone, date('now'));
     if (sqlca.sqlcode != 0) {
-	com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
-	exit(1);
+	if (sqlca.sqlcode == SQL_DEADLOCK) {
+	    com_err(whoami, MR_DEADLOCK, "adding user %s", sid);
+	    EXEC SQL ROLLBACK;
+	    return newuser(e);
+	} else {
+	    com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
+	    exit(1);
+	}
     } else
       com_err(whoami, 0, "adding user %s %s", e->first, e->last);
 }
@@ -670,7 +706,11 @@ set_next_uid(limit)
 
 sqlexit()
 {
-    com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
+    if (sqlca.sqlcode == SQL_DEADLOCK)
+      com_err(whoami, MR_DEADLOCK, "unrecoverable ingres error %d",
+	      sqlca.sqlcode);
+    else
+      com_err(whoami, 0, "ingres error %d", sqlca.sqlcode);
     EXEC SQL ROLLBACK WORK;
     exit(1);
 }
-- 
2.45.2