[v2] Added "--update-script" flag for specifying a command for running when new data piece is receviced.
Commit Message
Sometimes it's worth to work on data ASAP after they updated and there
is no time to wait for facters.
Signed-off-by: Anatoliy Lapitskiy <anatoliy.lapitskiy@gmail.com>"
---
alfred.h | 11 +++++++++++
main.c | 10 +++++++++-
man/alfred.8 | 4 ++++
recv.c | 9 ++++++++-
server.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 81 insertions(+), 2 deletions(-)
Comments
On Thursday 12 March 2015 13:06:01 Anatoliy Lapitskiy wrote:
> Sometimes it's worth to work on data ASAP after they updated and there
> is no time to wait for facters.
>
> Signed-off-by: Anatoliy Lapitskiy <anatoliy.lapitskiy@gmail.com>"
Why is there a double-quote at the end of the Signed-off-by?
The prefix "alfred: " is missing in the subject
The subject is quite long but the description is quite short.
Can you make the subject shorter and explain the rest better
in the description?
Further comments to the code can be found below.
> ---
> alfred.h | 11 +++++++++++
> main.c | 10 +++++++++-
> man/alfred.8 | 4 ++++
> recv.c | 9 ++++++++-
> server.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
> 5 files changed, 81 insertions(+), 2 deletions(-)
>
> diff --git a/alfred.h b/alfred.h
> index f26c80c..4eed67c 100644
> --- a/alfred.h
> +++ b/alfred.h
> @@ -55,6 +55,11 @@ struct dataset {
> uint8_t local_data;
> };
>
> +struct changed_data_type {
> + int data_type;
Data types are always uint8_t. Why are they becoming int here?
> + struct list_head list;
> +};
> +
> struct transaction_packet {
> struct alfred_push_data_v0 *push;
> struct list_head list;
> @@ -118,6 +123,10 @@ struct globals {
> int unix_sock;
> const char *unix_path;
>
> + const char *update_script;
> + struct list_head changed_data_types;
> + int changed_data_type_count;
> +
Why is the counter signed?
> struct timespec if_check;
>
> struct hashtable_t *data_hash;
> @@ -134,6 +143,8 @@ extern const struct in6_addr in6addr_localmcast;
> /* server.c */
> int alfred_server(struct globals *globals);
> int set_best_server(struct globals *globals);
> +void changed_data_type(struct globals *globals, int arg);
> +
Data types are always uint8_t. Why are they becoming int here?
> /* client.c */
> int alfred_client_request_data(struct globals *globals);
> int alfred_client_set_data(struct globals *globals);
> diff --git a/main.c b/main.c
> index e9821be..6b1a5d1 100644
> --- a/main.c
> +++ b/main.c
> @@ -61,6 +61,7 @@ static void alfred_usage(void)
> printf("\n");
> printf(" -u, --unix-path [path] path to unix socket used for client-server\n");
> printf(" communication (default: \""ALFRED_SOCK_PATH_DEFAULT"\")\n");
> + printf(" -c, --update-script path to script to call on data change\n");
> printf(" -v, --version print the version\n");
> printf(" -h, --help this help\n");
> printf("\n");
> @@ -153,6 +154,7 @@ static struct globals *alfred_init(int argc, char *argv[])
> {"modeswitch", required_argument, NULL, 'M'},
> {"change-interface", required_argument, NULL, 'I'},
> {"unix-path", required_argument, NULL, 'u'},
> + {"update-script", required_argument, NULL, 'c'},
> {"version", no_argument, NULL, 'v'},
> {"verbose", no_argument, NULL, 'd'},
> {NULL, 0, NULL, 0},
Fix your tabs here. Your line is unaligned starting with the required_argument
> @@ -174,10 +176,13 @@ static struct globals *alfred_init(int argc, char *argv[])
> globals->mesh_iface = "bat0";
> globals->unix_path = ALFRED_SOCK_PATH_DEFAULT;
> globals->verbose = 0;
> + globals->update_script = NULL;
> + INIT_LIST_HEAD(&globals->changed_data_types);
> + globals->changed_data_type_count = 0;
>
> time_random_seed();
>
> - while ((opt = getopt_long(argc, argv, "ms:r:hi:b:vV:M:I:u:d", long_options,
> + while ((opt = getopt_long(argc, argv, "ms:r:hi:b:vV:M:I:u:dc:", long_options,
> &opt_ind)) != -1) {
> switch (opt) {
> case 'r':
> @@ -237,6 +242,9 @@ static struct globals *alfred_init(int argc, char *argv[])
> case 'd':
> globals->verbose++;
> break;
> + case 'c':
> + globals->update_script = optarg;
> + break;
> case 'v':
> printf("%s %s\n", argv[0], SOURCE_VERSION);
> printf("A.L.F.R.E.D. - Almighty Lightweight Remote Fact Exchange Daemon\n");
> diff --git a/man/alfred.8 b/man/alfred.8
> index a8050ab..872e200 100644
> --- a/man/alfred.8
> +++ b/man/alfred.8
> @@ -114,6 +114,10 @@ still keeping redundancy (by having multiple masters). Obviously, at least one
> master must be present in the network to let any data exchange happen. Also
> having all nodes in master mode is possible (for maximum decentrality and
> overhead).
> +.TP
> +\fB\-c\fP, \fB\-\-update-script\fP \fIscriptname\fP
> +Specify path to script to call on data change. The script is called with
> +data-type list as arguments
> .
> .SH EXAMPLES
> Start an alfred server listening on bridge br0 (assuming that this bridge
> diff --git a/recv.c b/recv.c
> index e0252eb..0f6f50c 100644
> --- a/recv.c
> +++ b/recv.c
> @@ -40,7 +40,7 @@ static int finish_alfred_push_data(struct globals *globals,
> struct ether_addr mac,
> struct alfred_push_data_v0 *push)
> {
> - int len, data_len;
> + int len, data_len, new_entry;
> struct alfred_data *data;
> struct dataset *dataset;
> uint8_t *pos;
Has anyone a better name for new_entry? I don't really like it because
it sounds to me like a variable that stores the pointer to a new object.
> @@ -57,6 +57,7 @@ static int finish_alfred_push_data(struct globals *globals,
> if ((int)(data_len + sizeof(*data)) > len)
> break;
>
> + new_entry = 0;
> dataset = hash_find(globals->data_hash, data);
> if (!dataset) {
> dataset = malloc(sizeof(*dataset));
> @@ -71,6 +72,7 @@ static int finish_alfred_push_data(struct globals *globals,
> free(dataset);
> goto err;
> }
> + new_entry = 1;
> }
> /* don't overwrite our own data */
> if (dataset->data_source == SOURCE_LOCAL)
> @@ -78,6 +80,11 @@ static int finish_alfred_push_data(struct globals *globals,
>
> clock_gettime(CLOCK_MONOTONIC, &dataset->last_seen);
>
> + /* check that data was changed */
> + if (new_entry || dataset->data.header.length != data_len || memcmp(dataset->buf, data->data, data_len) != 0) {
> + changed_data_type(globals, data->header.type);
> + }
> +
Please reduce the length of your lines. I know that alfred is not always
using a maximum of 80 character per lines but we don't have to add more
of these overlong lines.
Dont use { } around single line scopes after if/while/for/...
> /* free old buffer */
> if (dataset->buf) {
> free(dataset->buf);
> diff --git a/server.c b/server.c
> index 1a3d876..f397de0 100644
> --- a/server.c
> +++ b/server.c
> @@ -23,6 +23,7 @@
> #include <inttypes.h>
> #include <net/ethernet.h>
> #include <net/if.h>
> +#include <signal.h>
> #include <stddef.h>
> #include <stdint.h>
> #include <stdio.h>
> @@ -138,6 +139,24 @@ int set_best_server(struct globals *globals)
> return 0;
> }
>
> +void changed_data_type(struct globals *globals, int arg)
> +{
> + if (!globals->update_script)
> + return;
> +
> + struct changed_data_type *data_type = NULL;
Please don't mix variable declarations and code. Try to keep the
declarations at the beginning.
> +
> + list_for_each_entry(data_type, &globals->changed_data_types, list) {
> + if (data_type->data_type == arg)
> + return;
> + }
> +
> + data_type = malloc(sizeof(*data_type));
> + data_type->data_type = arg;
> + list_add(&data_type->list, &globals->changed_data_types);
You are dereferencing something which could be NULL. Here from the
man page:
"On error, these functions return NULL."
> + globals->changed_data_type_count++;
> +}
> +
> static int purge_data(struct globals *globals)
> {
> struct hash_it_t *hashit = NULL;
> @@ -153,6 +172,8 @@ static int purge_data(struct globals *globals)
> if (diff.tv_sec < ALFRED_DATA_TIMEOUT)
> continue;
>
> + changed_data_type(globals, dataset->data.header.type);
> +
> hash_remove_bucket(globals->data_hash, hashit);
> free(dataset->buf);
> free(dataset);
> @@ -345,6 +366,34 @@ int alfred_server(struct globals *globals)
> }
> purge_data(globals);
> check_if_sockets(globals);
> +
> + if (globals->update_script && !list_empty(&globals->changed_data_types)) {
> + /* call update script with list of datatypes_changed */
> + char command[strlen(globals->update_script) + 7*globals->changed_data_type_count];
Please don't use variable length arrays.
Please fix your spacing around operands.
The calculation of the command length is complete bogus.
> + char buf[7];
> + strncpy(command, globals->update_script, sizeof(command));
Please make sure the the command is null terminated after strncpy.
Also add a blank line after the declarations.
Similar problem like the command buffer length... why the random chosen
number 7 for the buffer length? It is too small for your data type
(btw your data type for data_type is not fixed size), it doesn't include
space for the \0 byte at the end.
> +
> + struct changed_data_type *data_type, *is;
> + list_for_each_entry_safe(data_type, is, &globals->changed_data_types, list) {
> + /* append the datatype to command line */
> + snprintf(buf, sizeof(buf), " %d", data_type->data_type);
Please make sure the the command is null terminated after strncpy
Also add a blank line after the declarations.
Please don't mix variable declarations and code. Try to keep the
declarations at the beginning.
> + strncat(command, buf, sizeof(command) - strlen(command));
Make sure that there is enough room in command for the final \0 which is
appended by strncat. Currently it will just write over the end of the
buffer.
> +
> + /* clean the list */
> + list_del(&data_type->list);
> + free(data_type);
> + }
> +
> + printf("executing: %s\n", command);
> +
> + signal(SIGCHLD, SIG_IGN);
Why is the signal "handler" set always before fork?
> + int pid = fork();
> + if (pid == 0) {
> + system(command);
Why do you want to execute the command using the system shell? Maybe you
wanted to use something from the exec* family instead.
Please don't mix variable declarations and code. Try to keep the
declarations at the beginning.
> + exit(0);
> + }
> + globals->changed_data_type_count = 0;
> + }
> }
>
> netsock_close_all(globals);
>
Please move this large block to an extra function.
Maybe there are more thing but I have to stop the review now.
Kind regards,
Sven
Thank you very much for the review.
I have some notes below.
Anatoliy
On 03/13/2015 10:35 AM, Sven Eckelmann wrote:
> On Thursday 12 March 2015 13:06:01 Anatoliy Lapitskiy wrote:
>> Sometimes it's worth to work on data ASAP after they updated and there
>> is no time to wait for facters.
>>
>> Signed-off-by: Anatoliy Lapitskiy <anatoliy.lapitskiy@gmail.com>"
>
> Why is there a double-quote at the end of the Signed-off-by?
>
> The prefix "alfred: " is missing in the subject
>
> The subject is quite long but the description is quite short.
> Can you make the subject shorter and explain the rest better
> in the description?
>
> Further comments to the code can be found below.
>
>> ---
>> alfred.h | 11 +++++++++++
>> main.c | 10 +++++++++-
>> man/alfred.8 | 4 ++++
>> recv.c | 9 ++++++++-
>> server.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
>> 5 files changed, 81 insertions(+), 2 deletions(-)
>>
>> diff --git a/alfred.h b/alfred.h
>> index f26c80c..4eed67c 100644
>> --- a/alfred.h
>> +++ b/alfred.h
>> @@ -55,6 +55,11 @@ struct dataset {
>> uint8_t local_data;
>> };
>>
>> +struct changed_data_type {
>> + int data_type;
> Data types are always uint8_t. Why are they becoming int here?
>
>> + struct list_head list;
>> +};
>> +
>> struct transaction_packet {
>> struct alfred_push_data_v0 *push;
>> struct list_head list;
>> @@ -118,6 +123,10 @@ struct globals {
>> int unix_sock;
>> const char *unix_path;
>>
>> + const char *update_script;
>> + struct list_head changed_data_types;
>> + int changed_data_type_count;
>> +
> Why is the counter signed?
>
>> struct timespec if_check;
>>
>> struct hashtable_t *data_hash;
>> @@ -134,6 +143,8 @@ extern const struct in6_addr in6addr_localmcast;
>> /* server.c */
>> int alfred_server(struct globals *globals);
>> int set_best_server(struct globals *globals);
>> +void changed_data_type(struct globals *globals, int arg);
>> +
> Data types are always uint8_t. Why are they becoming int here?
>
>> /* client.c */
>> int alfred_client_request_data(struct globals *globals);
>> int alfred_client_set_data(struct globals *globals);
>> diff --git a/main.c b/main.c
>> index e9821be..6b1a5d1 100644
>> --- a/main.c
>> +++ b/main.c
>> @@ -61,6 +61,7 @@ static void alfred_usage(void)
>> printf("\n");
>> printf(" -u, --unix-path [path] path to unix socket used for client-server\n");
>> printf(" communication (default: \""ALFRED_SOCK_PATH_DEFAULT"\")\n");
>> + printf(" -c, --update-script path to script to call on data change\n");
>> printf(" -v, --version print the version\n");
>> printf(" -h, --help this help\n");
>> printf("\n");
>> @@ -153,6 +154,7 @@ static struct globals *alfred_init(int argc, char *argv[])
>> {"modeswitch", required_argument, NULL, 'M'},
>> {"change-interface", required_argument, NULL, 'I'},
>> {"unix-path", required_argument, NULL, 'u'},
>> + {"update-script", required_argument, NULL, 'c'},
>> {"version", no_argument, NULL, 'v'},
>> {"verbose", no_argument, NULL, 'd'},
>> {NULL, 0, NULL, 0},
> Fix your tabs here. Your line is unaligned starting with the required_argument
>
>> @@ -174,10 +176,13 @@ static struct globals *alfred_init(int argc, char *argv[])
>> globals->mesh_iface = "bat0";
>> globals->unix_path = ALFRED_SOCK_PATH_DEFAULT;
>> globals->verbose = 0;
>> + globals->update_script = NULL;
>> + INIT_LIST_HEAD(&globals->changed_data_types);
>> + globals->changed_data_type_count = 0;
>>
>> time_random_seed();
>>
>> - while ((opt = getopt_long(argc, argv, "ms:r:hi:b:vV:M:I:u:d", long_options,
>> + while ((opt = getopt_long(argc, argv, "ms:r:hi:b:vV:M:I:u:dc:", long_options,
>> &opt_ind)) != -1) {
>> switch (opt) {
>> case 'r':
>> @@ -237,6 +242,9 @@ static struct globals *alfred_init(int argc, char *argv[])
>> case 'd':
>> globals->verbose++;
>> break;
>> + case 'c':
>> + globals->update_script = optarg;
>> + break;
>> case 'v':
>> printf("%s %s\n", argv[0], SOURCE_VERSION);
>> printf("A.L.F.R.E.D. - Almighty Lightweight Remote Fact Exchange Daemon\n");
>> diff --git a/man/alfred.8 b/man/alfred.8
>> index a8050ab..872e200 100644
>> --- a/man/alfred.8
>> +++ b/man/alfred.8
>> @@ -114,6 +114,10 @@ still keeping redundancy (by having multiple masters). Obviously, at least one
>> master must be present in the network to let any data exchange happen. Also
>> having all nodes in master mode is possible (for maximum decentrality and
>> overhead).
>> +.TP
>> +\fB\-c\fP, \fB\-\-update-script\fP \fIscriptname\fP
>> +Specify path to script to call on data change. The script is called with
>> +data-type list as arguments
>> .
>> .SH EXAMPLES
>> Start an alfred server listening on bridge br0 (assuming that this bridge
>> diff --git a/recv.c b/recv.c
>> index e0252eb..0f6f50c 100644
>> --- a/recv.c
>> +++ b/recv.c
>> @@ -40,7 +40,7 @@ static int finish_alfred_push_data(struct globals *globals,
>> struct ether_addr mac,
>> struct alfred_push_data_v0 *push)
>> {
>> - int len, data_len;
>> + int len, data_len, new_entry;
>> struct alfred_data *data;
>> struct dataset *dataset;
>> uint8_t *pos;
> Has anyone a better name for new_entry? I don't really like it because
> it sounds to me like a variable that stores the pointer to a new object.
"new_entry_created"?
btw, it could be bool as it's just a flag. can I use <stdbool.h> from C99?
>
>> @@ -57,6 +57,7 @@ static int finish_alfred_push_data(struct globals *globals,
>> if ((int)(data_len + sizeof(*data)) > len)
>> break;
>>
>> + new_entry = 0;
>> dataset = hash_find(globals->data_hash, data);
>> if (!dataset) {
>> dataset = malloc(sizeof(*dataset));
>> @@ -71,6 +72,7 @@ static int finish_alfred_push_data(struct globals *globals,
>> free(dataset);
>> goto err;
>> }
>> + new_entry = 1;
>> }
>> /* don't overwrite our own data */
>> if (dataset->data_source == SOURCE_LOCAL)
>> @@ -78,6 +80,11 @@ static int finish_alfred_push_data(struct globals *globals,
>>
>> clock_gettime(CLOCK_MONOTONIC, &dataset->last_seen);
>>
>> + /* check that data was changed */
>> + if (new_entry || dataset->data.header.length != data_len || memcmp(dataset->buf, data->data, data_len) != 0) {
>> + changed_data_type(globals, data->header.type);
>> + }
>> +
> Please reduce the length of your lines. I know that alfred is not always
> using a maximum of 80 character per lines but we don't have to add more
> of these overlong lines.
>
> Dont use { } around single line scopes after if/while/for/...
>
>> /* free old buffer */
>> if (dataset->buf) {
>> free(dataset->buf);
>> diff --git a/server.c b/server.c
>> index 1a3d876..f397de0 100644
>> --- a/server.c
>> +++ b/server.c
>> @@ -23,6 +23,7 @@
>> #include <inttypes.h>
>> #include <net/ethernet.h>
>> #include <net/if.h>
>> +#include <signal.h>
>> #include <stddef.h>
>> #include <stdint.h>
>> #include <stdio.h>
>> @@ -138,6 +139,24 @@ int set_best_server(struct globals *globals)
>> return 0;
>> }
>>
>> +void changed_data_type(struct globals *globals, int arg)
>> +{
>> + if (!globals->update_script)
>> + return;
>> +
>> + struct changed_data_type *data_type = NULL;
> Please don't mix variable declarations and code. Try to keep the
> declarations at the beginning.
>
>> +
>> + list_for_each_entry(data_type, &globals->changed_data_types, list) {
>> + if (data_type->data_type == arg)
>> + return;
>> + }
>> +
>> + data_type = malloc(sizeof(*data_type));
>> + data_type->data_type = arg;
>> + list_add(&data_type->list, &globals->changed_data_types);
> You are dereferencing something which could be NULL. Here from the
> man page:
>
> "On error, these functions return NULL."
>
>> + globals->changed_data_type_count++;
>> +}
>> +
>> static int purge_data(struct globals *globals)
>> {
>> struct hash_it_t *hashit = NULL;
>> @@ -153,6 +172,8 @@ static int purge_data(struct globals *globals)
>> if (diff.tv_sec < ALFRED_DATA_TIMEOUT)
>> continue;
>>
>> + changed_data_type(globals, dataset->data.header.type);
>> +
>> hash_remove_bucket(globals->data_hash, hashit);
>> free(dataset->buf);
>> free(dataset);
>> @@ -345,6 +366,34 @@ int alfred_server(struct globals *globals)
>> }
>> purge_data(globals);
>> check_if_sockets(globals);
>> +
>> + if (globals->update_script && !list_empty(&globals->changed_data_types)) {
>> + /* call update script with list of datatypes_changed */
>> + char command[strlen(globals->update_script) + 7*globals->changed_data_type_count];
> Please don't use variable length arrays.
>
> Please fix your spacing around operands.
>
> The calculation of the command length is complete bogus.
Agree. it should be length of update_script + 4 * changed count (3 for data type as maximum is "255" + space) + 1 for NULL.
I will add a comment about it.
>
>> + char buf[7];
>> + strncpy(command, globals->update_script, sizeof(command));
> Please make sure the the command is null terminated after strncpy.
>
> Also add a blank line after the declarations.
>
> Similar problem like the command buffer length... why the random chosen
> number 7 for the buffer length? It is too small for your data type
> (btw your data type for data_type is not fixed size), it doesn't include
> space for the \0 byte at the end.
yes, 7 isn't correct number. The correct number is 5 (3 for data type which is 255 maximum + 1 for space + 1 for NULL)
I will add a comment about it.
>
>> +
>> + struct changed_data_type *data_type, *is;
>> + list_for_each_entry_safe(data_type, is, &globals->changed_data_types, list) {
>> + /* append the datatype to command line */
>> + snprintf(buf, sizeof(buf), " %d", data_type->data_type);
> Please make sure the the command is null terminated after strncpy
>
> Also add a blank line after the declarations.
>
> Please don't mix variable declarations and code. Try to keep the
> declarations at the beginning.
>
>> + strncat(command, buf, sizeof(command) - strlen(command));
> Make sure that there is enough room in command for the final \0 which is
> appended by strncat. Currently it will just write over the end of the
> buffer.
>
>> +
>> + /* clean the list */
>> + list_del(&data_type->list);
>> + free(data_type);
>> + }
>> +
>> + printf("executing: %s\n", command);
>> +
>> + signal(SIGCHLD, SIG_IGN);
> Why is the signal "handler" set always before fork?
>
>> + int pid = fork();
>> + if (pid == 0) {
>> + system(command);
> Why do you want to execute the command using the system shell? Maybe you
> wanted to use something from the exec* family instead.
In case if user will set shell script as "update-script" parameter, exec* won't work.
Of course, I can add "sh", "-c" to exec* parameters, but what advantages this method will have then?
>
> Please don't mix variable declarations and code. Try to keep the
> declarations at the beginning.
>
>> + exit(0);
>> + }
>> + globals->changed_data_type_count = 0;
>> + }
>> }
>>
>> netsock_close_all(globals);
>>
> Please move this large block to an extra function.
>
> Maybe there are more thing but I have to stop the review now.
Again, thank you very much for review.
Is there a link for code style used?
>
> Kind regards,
> Sven
>
On Friday 13 March 2015 12:28:15 Anatoliy wrote:
[...]
> >> --- a/recv.c
> >> +++ b/recv.c
> >> @@ -40,7 +40,7 @@ static int finish_alfred_push_data(struct globals *globals,
> >> struct ether_addr mac,
> >> struct alfred_push_data_v0 *push)
> >> {
> >> - int len, data_len;
> >> + int len, data_len, new_entry;
> >> struct alfred_data *data;
> >> struct dataset *dataset;
> >> uint8_t *pos;
> > Has anyone a better name for new_entry? I don't really like it because
> > it sounds to me like a variable that stores the pointer to a new object.
> "new_entry_created"?
> btw, it could be bool as it's just a flag. can I use <stdbool.h> from C99?
Yes, sounds good. I personally have nothing against bool.
(At least not at the moment)
[...]
> >> +
> >> + if (globals->update_script && !list_empty(&globals->changed_data_types)) {
> >> + /* call update script with list of datatypes_changed */
> >> + char command[strlen(globals->update_script) + 7*globals->changed_data_type_count];
> > Please don't use variable length arrays.
> >
> > Please fix your spacing around operands.
> >
> > The calculation of the command length is complete bogus.
> Agree. it should be length of update_script + 4 * changed count (3 for data type as maximum is "255" + space) + 1 for NULL.
> I will add a comment about it.
Please don't forget the change of the datatype of data_type to really
have a range of 0-255.
I don't think the comment is important but we will see if it is helpful.
[...]
> >> + int pid = fork();
> >> + if (pid == 0) {
> >> + system(command);
> > Why do you want to execute the command using the system shell? Maybe you
> > wanted to use something from the exec* family instead.
> In case if user will set shell script as "update-script" parameter, exec* won't work.
> Of course, I can add "sh", "-c" to exec* parameters, but what advantages this method will have then?
This was exactly the thing I wanted to know. If you really want to
support shell scripts then please update your manpage entry to
inform the user about this "feature". Otherwise he might
accidentally forget the required escaping or similar things.
Currently the manpage says that you can specify a path and not a
script which may be used to execute a file.
[...]
> >
> > Maybe there are more thing but I have to stop the review now.
> Again, thank you very much for review.
> Is there a link for code style used?
* http://www.open-mesh.org/projects/open-mesh/wiki/Contribute#Submitting-patches
* https://www.kernel.org/doc/Documentation/CodingStyle
* the mood of the person reviewing the code
Kind regards,
Sven
@@ -55,6 +55,11 @@ struct dataset {
uint8_t local_data;
};
+struct changed_data_type {
+ int data_type;
+ struct list_head list;
+};
+
struct transaction_packet {
struct alfred_push_data_v0 *push;
struct list_head list;
@@ -118,6 +123,10 @@ struct globals {
int unix_sock;
const char *unix_path;
+ const char *update_script;
+ struct list_head changed_data_types;
+ int changed_data_type_count;
+
struct timespec if_check;
struct hashtable_t *data_hash;
@@ -134,6 +143,8 @@ extern const struct in6_addr in6addr_localmcast;
/* server.c */
int alfred_server(struct globals *globals);
int set_best_server(struct globals *globals);
+void changed_data_type(struct globals *globals, int arg);
+
/* client.c */
int alfred_client_request_data(struct globals *globals);
int alfred_client_set_data(struct globals *globals);
@@ -61,6 +61,7 @@ static void alfred_usage(void)
printf("\n");
printf(" -u, --unix-path [path] path to unix socket used for client-server\n");
printf(" communication (default: \""ALFRED_SOCK_PATH_DEFAULT"\")\n");
+ printf(" -c, --update-script path to script to call on data change\n");
printf(" -v, --version print the version\n");
printf(" -h, --help this help\n");
printf("\n");
@@ -153,6 +154,7 @@ static struct globals *alfred_init(int argc, char *argv[])
{"modeswitch", required_argument, NULL, 'M'},
{"change-interface", required_argument, NULL, 'I'},
{"unix-path", required_argument, NULL, 'u'},
+ {"update-script", required_argument, NULL, 'c'},
{"version", no_argument, NULL, 'v'},
{"verbose", no_argument, NULL, 'd'},
{NULL, 0, NULL, 0},
@@ -174,10 +176,13 @@ static struct globals *alfred_init(int argc, char *argv[])
globals->mesh_iface = "bat0";
globals->unix_path = ALFRED_SOCK_PATH_DEFAULT;
globals->verbose = 0;
+ globals->update_script = NULL;
+ INIT_LIST_HEAD(&globals->changed_data_types);
+ globals->changed_data_type_count = 0;
time_random_seed();
- while ((opt = getopt_long(argc, argv, "ms:r:hi:b:vV:M:I:u:d", long_options,
+ while ((opt = getopt_long(argc, argv, "ms:r:hi:b:vV:M:I:u:dc:", long_options,
&opt_ind)) != -1) {
switch (opt) {
case 'r':
@@ -237,6 +242,9 @@ static struct globals *alfred_init(int argc, char *argv[])
case 'd':
globals->verbose++;
break;
+ case 'c':
+ globals->update_script = optarg;
+ break;
case 'v':
printf("%s %s\n", argv[0], SOURCE_VERSION);
printf("A.L.F.R.E.D. - Almighty Lightweight Remote Fact Exchange Daemon\n");
@@ -114,6 +114,10 @@ still keeping redundancy (by having multiple masters). Obviously, at least one
master must be present in the network to let any data exchange happen. Also
having all nodes in master mode is possible (for maximum decentrality and
overhead).
+.TP
+\fB\-c\fP, \fB\-\-update-script\fP \fIscriptname\fP
+Specify path to script to call on data change. The script is called with
+data-type list as arguments
.
.SH EXAMPLES
Start an alfred server listening on bridge br0 (assuming that this bridge
@@ -40,7 +40,7 @@ static int finish_alfred_push_data(struct globals *globals,
struct ether_addr mac,
struct alfred_push_data_v0 *push)
{
- int len, data_len;
+ int len, data_len, new_entry;
struct alfred_data *data;
struct dataset *dataset;
uint8_t *pos;
@@ -57,6 +57,7 @@ static int finish_alfred_push_data(struct globals *globals,
if ((int)(data_len + sizeof(*data)) > len)
break;
+ new_entry = 0;
dataset = hash_find(globals->data_hash, data);
if (!dataset) {
dataset = malloc(sizeof(*dataset));
@@ -71,6 +72,7 @@ static int finish_alfred_push_data(struct globals *globals,
free(dataset);
goto err;
}
+ new_entry = 1;
}
/* don't overwrite our own data */
if (dataset->data_source == SOURCE_LOCAL)
@@ -78,6 +80,11 @@ static int finish_alfred_push_data(struct globals *globals,
clock_gettime(CLOCK_MONOTONIC, &dataset->last_seen);
+ /* check that data was changed */
+ if (new_entry || dataset->data.header.length != data_len || memcmp(dataset->buf, data->data, data_len) != 0) {
+ changed_data_type(globals, data->header.type);
+ }
+
/* free old buffer */
if (dataset->buf) {
free(dataset->buf);
@@ -23,6 +23,7 @@
#include <inttypes.h>
#include <net/ethernet.h>
#include <net/if.h>
+#include <signal.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
@@ -138,6 +139,24 @@ int set_best_server(struct globals *globals)
return 0;
}
+void changed_data_type(struct globals *globals, int arg)
+{
+ if (!globals->update_script)
+ return;
+
+ struct changed_data_type *data_type = NULL;
+
+ list_for_each_entry(data_type, &globals->changed_data_types, list) {
+ if (data_type->data_type == arg)
+ return;
+ }
+
+ data_type = malloc(sizeof(*data_type));
+ data_type->data_type = arg;
+ list_add(&data_type->list, &globals->changed_data_types);
+ globals->changed_data_type_count++;
+}
+
static int purge_data(struct globals *globals)
{
struct hash_it_t *hashit = NULL;
@@ -153,6 +172,8 @@ static int purge_data(struct globals *globals)
if (diff.tv_sec < ALFRED_DATA_TIMEOUT)
continue;
+ changed_data_type(globals, dataset->data.header.type);
+
hash_remove_bucket(globals->data_hash, hashit);
free(dataset->buf);
free(dataset);
@@ -345,6 +366,34 @@ int alfred_server(struct globals *globals)
}
purge_data(globals);
check_if_sockets(globals);
+
+ if (globals->update_script && !list_empty(&globals->changed_data_types)) {
+ /* call update script with list of datatypes_changed */
+ char command[strlen(globals->update_script) + 7*globals->changed_data_type_count];
+ char buf[7];
+ strncpy(command, globals->update_script, sizeof(command));
+
+ struct changed_data_type *data_type, *is;
+ list_for_each_entry_safe(data_type, is, &globals->changed_data_types, list) {
+ /* append the datatype to command line */
+ snprintf(buf, sizeof(buf), " %d", data_type->data_type);
+ strncat(command, buf, sizeof(command) - strlen(command));
+
+ /* clean the list */
+ list_del(&data_type->list);
+ free(data_type);
+ }
+
+ printf("executing: %s\n", command);
+
+ signal(SIGCHLD, SIG_IGN);
+ int pid = fork();
+ if (pid == 0) {
+ system(command);
+ exit(0);
+ }
+ globals->changed_data_type_count = 0;
+ }
}
netsock_close_all(globals);