Add the ability to query configuration variables to tincctl.

diff --git a/doc/tinc.texi b/doc/tinc.texi
index 40a297a..b2236b4 100644 (file)
--- a/doc/tinc.texi
+++ b/doc/tinc.texi
@@ -2044,6 +2044,11 @@ the value of this environment variable is used.
 Create initial configuration files and RSA and ECDSA keypairs with default length.
 If no @var{name} for this node is given, it will be asked for.
 
+@item config [get] @var{variable}
+Print the current value of configuration variable @var{variable}.
+If more than one variable with the same name exists,
+the value of each of them will be printed on a separate line.
+
 @item config [set] @var{variable} @var{value}
 Set configuration variable @var{variable} to the given @var{value}.
 All previously existing configuration variables with the same name are removed.

diff --git a/doc/tincctl.8.in b/doc/tincctl.8.in
index 4b6d426..3ca6753 100644 (file)
--- a/doc/tincctl.8.in
+++ b/doc/tincctl.8.in
@@ -52,6 +52,11 @@ Create initial configuration files and RSA and ECDSA keypairs with default lengt
 If no
 .Ar name
 for this node is given, it will be asked for.
+.It config Oo get Oc Ar variable
+Print the current value of configuration variable
+.Ar variable .
+If more than one variable with the same name exists,
+the value of each of them will be printed on a separate line.
 .It config Oo set Oc Ar variable Ar value
 Set configuration variable
 .Ar variable

diff --git a/src/tincctl.c b/src/tincctl.c
index 188db92..64340c7 100644 (file)
--- a/src/tincctl.c
+++ b/src/tincctl.c
@@ -111,6 +111,7 @@ static void usage(bool status) {
                                "Valid commands are:\n"
                                "  init [name]                Create initial configuration files.\n"
                                "  config                     Change configuration:\n"
+                               "    [get] VARIABLE           - print current value of VARIABLE\n"
                                "    [set] VARIABLE VALUE     - set VARIABLE to VALUE\n"
                                "    add VARIABLE VALUE       - add VARIABLE with the given VALUE\n"
                                "    del VARIABLE [VALUE]     - remove VARIABLE [only ones with watching VALUE]\n"
@@ -942,7 +943,7 @@ static int cmd_log(int argc, char *argv[]) {
 }
 
 static int cmd_pid(int argc, char *argv[]) {
-       if(!connect_tincd())
+       if(!connect_tincd() && !pid)
                return 1;
 
        printf("%d\n", pid);
@@ -1056,8 +1057,10 @@ static int cmd_config(int argc, char *argv[]) {
                return 1;
        }
 
-       int action = 0;
-       if(!strcasecmp(argv[1], "add")) {
+       int action = -2;
+       if(!strcasecmp(argv[1], "get")) {
+               argv++, argc--;
+       } else if(!strcasecmp(argv[1], "add")) {
                argv++, argc--, action = 1;
        } else if(!strcasecmp(argv[1], "del")) {
                argv++, argc--, action = -1;
@@ -1109,6 +1112,9 @@ static int cmd_config(int argc, char *argv[]) {
                return 1;
        }
 
+       if(action < -1 && *value)
+               action = 0;
+
        /* Some simple checks. */
        bool found = false;
 
@@ -1157,8 +1163,8 @@ static int cmd_config(int argc, char *argv[]) {
                return 1;
        }
 
-       if(!found && action >= 0) {
-               if(force) {
+       if(!found) {
+               if(force || action < 0) {
                        fprintf(stderr, "Warning: %s is not a known configuration variable!\n", variable);
                } else {
                        fprintf(stderr, "%s: is not a known configuration variable! Use --force to use it anyway.\n", variable);
@@ -1190,19 +1196,24 @@ static int cmd_config(int argc, char *argv[]) {
                }
        }
 
-       char *tmpfile;
-       xasprintf(&tmpfile, "%s.config.tmp", filename);
-       FILE *tf = fopen(tmpfile, "w");
-       if(!tf) {
-               fprintf(stderr, "Could not open temporary file %s: %s\n", tmpfile, strerror(errno));
-               return 1;
+       char *tmpfile = NULL;
+       FILE *tf = NULL;
+
+       if(action >= -1) {
+               xasprintf(&tmpfile, "%s.config.tmp", filename);
+               tf = fopen(tmpfile, "w");
+               if(!tf) {
+                       fprintf(stderr, "Could not open temporary file %s: %s\n", tmpfile, strerror(errno));
+                       return 1;
+               }
        }
 
-       // Copy the file, making modifications on the fly.
+       // Copy the file, making modifications on the fly, unless we are just getting a value.
        char buf1[4096];
        char buf2[4096];
        bool set = false;
        bool removed = false;
+       found = false;
 
        while(fgets(buf1, sizeof buf1, f)) {
                buf1[sizeof buf1 - 1] = 0;
@@ -1224,8 +1235,12 @@ static int cmd_config(int argc, char *argv[]) {
 
                // Did it match?
                if(!strcasecmp(buf2, variable)) {
+                       // Get
+                       if(action < -1) {
+                               found = true;
+                               printf("%s\n", bvalue);
                        // Del
-                       if(action < 0) {
+                       } else if(action == -1) {
                                if(!*value || !strcasecmp(bvalue, value)) {
                                        removed = true;
                                        continue;
@@ -1245,18 +1260,20 @@ static int cmd_config(int argc, char *argv[]) {
                        }
                }
 
-               // Copy original line...
-               if(fputs(buf1, tf) < 0) {
-                       fprintf(stderr, "Error writing to temporary file %s: %s\n", tmpfile, strerror(errno));
-                       return 1;
-               }
-
-               // Add newline if it is missing...
-               if(*buf1 && buf1[strlen(buf1) - 1] != '\n') {
-                       if(fputc('\n', tf) < 0) {
+               if(action >= -1) {
+                       // Copy original line...
+                       if(fputs(buf1, tf) < 0) {
                                fprintf(stderr, "Error writing to temporary file %s: %s\n", tmpfile, strerror(errno));
                                return 1;
                        }
+
+                       // Add newline if it is missing...
+                       if(*buf1 && buf1[strlen(buf1) - 1] != '\n') {
+                               if(fputc('\n', tf) < 0) {
+                                       fprintf(stderr, "Error writing to temporary file %s: %s\n", tmpfile, strerror(errno));
+                                       return 1;
+                               }
+                       }
                }
        }
 
@@ -1279,6 +1296,12 @@ static int cmd_config(int argc, char *argv[]) {
                }
        }
 
+       if(action < -1) {
+               if(!found)
+                       fprintf(stderr, "No matching configuration variables found.\n");
+               return 0;
+       }
+
        // Make sure we wrote everything...
        if(fclose(tf)) {
                fprintf(stderr, "Error closing temporary file %s: %s\n", tmpfile, strerror(errno));