Allow checking that databases are up to date even when you have no write

permission on the databases, as requested by espie@ quite some time ago.
But make sure to not slow database generation down when you do have write
permission, and to not delay error reporting in -Q mode.

diff --git a/mandocdb.c b/mandocdb.c
index eea9ab1cf0c18cae74d0534b76b67db3236ae1e9..cea720ac6f9a6e7a820f99d49ac44646cd0df4e1 100644 (file)
--- a/mandocdb.c
+++ b/mandocdb.c
@@ -1,4 +1,4 @@
-/*     $Id: mandocdb.c,v 1.114 2014/01/22 20:58:39 schwarze Exp $ */
+/*     $Id: mandocdb.c,v 1.115 2014/03/18 16:56:10 schwarze Exp $ */
 /*
  * Copyright (c) 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2011, 2012, 2013, 2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -20,6 +20,7 @@
 #endif
 
 #include <sys/stat.h>
+#include <sys/wait.h>
 
 #include <assert.h>
 #include <ctype.h>
@@ -168,6 +169,7 @@ static      int      set_basedir(const char *);
 static int      treescan(void);
 static size_t   utf8(unsigned int, char [7]);
 
+static char             tempfilename[32];
 static char            *progname;
 static int              nodb; /* no database changes */
 static int              quick; /* abort the parse early */
@@ -1874,6 +1876,8 @@ static void
 dbclose(int real)
 {
        size_t           i;
+       int              status;
+       pid_t            child;
 
        if (nodb)
                return;
@@ -1889,9 +1893,59 @@ dbclose(int real)
        if (real)
                return;
 
-       if (-1 == rename(MANDOC_DB "~", MANDOC_DB)) {
+       if ('\0' == *tempfilename) {
+               if (-1 == rename(MANDOC_DB "~", MANDOC_DB)) {
+                       exitcode = (int)MANDOCLEVEL_SYSERR;
+                       say(MANDOC_DB, "%s", strerror(errno));
+               }
+               return;
+       }
+
+       switch (child = fork()) {
+       case (-1):
+               exitcode = (int)MANDOCLEVEL_SYSERR;
+               say("fork cmp", "%s", strerror(errno));
+               return;
+       case (0):
+               execlp("cmp", "cmp", "-s",
+                   tempfilename, MANDOC_DB, NULL);
+               say("exec cmp", "%s", strerror(errno));
+               exit(0);
+       default:
+               break;
+       }
+       if (-1 == waitpid(child, &status, 0)) {
+               exitcode = (int)MANDOCLEVEL_SYSERR;
+               say("wait cmp", "%s", strerror(errno));
+       } else if (WIFSIGNALED(status)) {
+               exitcode = (int)MANDOCLEVEL_SYSERR;
+               say("cmp", "Died from a signal");
+       } else if (WEXITSTATUS(status)) {
                exitcode = (int)MANDOCLEVEL_SYSERR;
-               say(MANDOC_DB, NULL);
+               say(MANDOC_DB,
+                   "Data changed, but cannot replace database");
+       }
+
+       *strrchr(tempfilename, '/') = '\0';
+       switch (child = fork()) {
+       case (-1):
+               exitcode = (int)MANDOCLEVEL_SYSERR;
+               say("fork rm", "%s", strerror(errno));
+               return;
+       case (0):
+               execlp("rm", "rm", "-rf", tempfilename, NULL);
+               say("exec rm", "%s", strerror(errno));
+               exit((int)MANDOCLEVEL_SYSERR);
+       default:
+               break;
+       }
+       if (-1 == waitpid(child, &status, 0)) {
+               exitcode = (int)MANDOCLEVEL_SYSERR;
+               say("wait rm", "%s", strerror(errno));
+       } else if (WIFSIGNALED(status) || WEXITSTATUS(status)) {
+               exitcode = (int)MANDOCLEVEL_SYSERR;
+               say(tempfilename,
+                   "Cannot remove temporary directory");
        }
 }
 
@@ -1906,42 +1960,62 @@ dbclose(int real)
 static int
 dbopen(int real)
 {
-       const char      *file, *sql;
+       const char      *sql;
        int              rc, ofl;
 
        if (nodb) 
                return(1);
 
+       *tempfilename = '\0';
        ofl = SQLITE_OPEN_READWRITE;
-       if (0 == real) {
-               file = MANDOC_DB "~";
-               if (-1 == remove(file) && ENOENT != errno) {
+
+       if (real) {
+               rc = sqlite3_open_v2(MANDOC_DB, &db, ofl, NULL);
+               if (SQLITE_OK != rc) {
                        exitcode = (int)MANDOCLEVEL_SYSERR;
-                       say(file, NULL);
+                       say(MANDOC_DB, "%s", sqlite3_errmsg(db));
                        return(0);
                }
-               ofl |= SQLITE_OPEN_EXCLUSIVE;
-       } else
-               file = MANDOC_DB;
+               goto prepare_statements;
+       }
 
-       rc = sqlite3_open_v2(file, &db, ofl, NULL);
+       ofl |= SQLITE_OPEN_CREATE | SQLITE_OPEN_EXCLUSIVE;
+
+       remove(MANDOC_DB "~");
+       rc = sqlite3_open_v2(MANDOC_DB "~", &db, ofl, NULL);
        if (SQLITE_OK == rc) 
-               goto prepare_statements;
-       if (SQLITE_CANTOPEN != rc) {
+               goto create_tables;
+       if (quick) {
                exitcode = (int)MANDOCLEVEL_SYSERR;
-               say(file, NULL);
+               say(MANDOC_DB "~", "%s", sqlite3_errmsg(db));
                return(0);
        }
 
-       sqlite3_close(db);
-       db = NULL;
-
-       if (SQLITE_OK != (rc = sqlite3_open(file, &db))) {
+       if (strlcpy(tempfilename, "/tmp/mandocdb.XXXXXX",
+           sizeof(tempfilename)) >= sizeof(tempfilename)) {
                exitcode = (int)MANDOCLEVEL_SYSERR;
-               say(file, NULL);
+               say("/tmp/mandocdb.XXXXXX", "Filename too long");
+               return(0);
+       }
+       if (NULL == mkdtemp(tempfilename)) {
+               exitcode = (int)MANDOCLEVEL_SYSERR;
+               say(tempfilename, "%s", strerror(errno));
+               return(0);
+       }
+       if (strlcat(tempfilename, "/" MANDOC_DB,
+           sizeof(tempfilename)) >= sizeof(tempfilename)) {
+               exitcode = (int)MANDOCLEVEL_SYSERR;
+               say(tempfilename, "Filename too long");
+               return(0);
+       }
+       rc = sqlite3_open_v2(tempfilename, &db, ofl, NULL);
+       if (SQLITE_OK != rc) {
+               exitcode = (int)MANDOCLEVEL_SYSERR;
+               say(tempfilename, "%s", sqlite3_errmsg(db));
                return(0);
        }
 
+create_tables:
        sql = "CREATE TABLE \"mpages\" (\n"
              " \"form\" INTEGER NOT NULL,\n"
              " \"id\" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL\n"
@@ -1964,7 +2038,7 @@ dbopen(int real)
 
        if (SQLITE_OK != sqlite3_exec(db, sql, NULL, NULL, NULL)) {
                exitcode = (int)MANDOCLEVEL_SYSERR;
-               say(file, "%s", sqlite3_errmsg(db));
+               say(MANDOC_DB, "%s", sqlite3_errmsg(db));
                return(0);
        }