Hi, all.
what about generating the man page on the basis of the btrfs help
detailed messages ?
My idea is the following:
before the function source associated to the command we can put a
comment with a detailed help. The comment may be:
[...]
/*** man:btrfs subvolume create
*
* btrfs subvolume create <path>
* create a new subvolume
*
* The command [b]btrfs subvolume create[b] is used.....
*
***/
void do_create_subvolume(int argc, char **argv)
{
[...]
A script extracts from the comment in the source both:
- the text for the man page
- the text for the detailed help.
So we can reach the following goals:
- the help is linked to the code
- is less likely to forget to update the message
- the man page, the helps are always aligned
BR
G.Baroncelli
On 07/11/2011 05:13 PM, Jan Schmidt wrote:
> Hi Hubert,
>
> I have to admit I did not recognize this patch but now Hugo is forcing
> me to use the "detailed help messages" and I've got an improvement to
> suggest:
>
> On 23.01.2011 13:42, Hubert Kario wrote:
>> extend the
>>
>> btrfs <cmd> --help
>>
>> command to print detailed help message if available but fallback to
>> basic help message if detailed is unavailable
>>
>> add detailed help message for 'filesystem defragment' command
>>
>> little tweaks in comments
>>
>> Signed-off-by: Hubert Kario <kario@xxxxxxxxxx>
>> ---
>> btrfs.c | 101 ++++++++++++++++++++++++++++++++++++++++++--------------------
>> 1 files changed, 68 insertions(+), 33 deletions(-)
>>
>> diff --git a/btrfs.c b/btrfs.c
>> index b84607a..bd6f6f8 100644
>> --- a/btrfs.c
>> +++ b/btrfs.c
>> @@ -23,6 +23,9 @@
>> #include "btrfs_cmds.h"
>> #include "version.h"
>>
>> +#define BASIC_HELP 0
>> +#define ADVANCED_HELP 1
>> +
>> typedef int (*CommandFunction)(int argc, char **argv);
>>
>> struct Command {
>> @@ -31,8 +34,10 @@ struct Command {
>> if >= 0, number of arguments,
>> if < 0, _minimum_ number of arguments */
>> char *verb; /* verb */
>> - char *help; /* help lines; form the 2nd onward they are
>> - indented */
>> + char *help; /* help lines; from the 2nd line onward they
>> + are automatically indented */
>> + char *adv_help; /* advanced help message; from the 2nd line
>> + onward they are automatically indented */
>> /* the following fields are run-time filled by the program */
>> char **cmds; /* array of subcommands */
>> @@ -47,73 +52,96 @@ static struct Command commands[] = {
>> { do_clone, 2,
>> "subvolume snapshot", "<source> [<dest>/]<name>\n"
>> "Create a writable snapshot of the subvolume <source> with\n"
>> - "the name <name> in the <dest> directory."
>> + "the name <name> in the <dest> directory.",
>> + NULL
>> },
>> { do_delete_subvolume, 1,
>> "subvolume delete", "<subvolume>\n"
>> - "Delete the subvolume <subvolume>."
>> + "Delete the subvolume <subvolume>.",
>> + NULL
>> },
>> { do_create_subvol, 1,
>> "subvolume create", "[<dest>/]<name>\n"
>> "Create a subvolume in <dest> (or the current directory if\n"
>> - "not passed)."
>> + "not passed).",
>> + NULL
>> },
>> { do_subvol_list, 1, "subvolume list", "<path>\n"
>> - "List the snapshot/subvolume of a filesystem."
>> + "List the snapshot/subvolume of a filesystem.",
>> + NULL
>> },
>> { do_find_newer, 2, "subvolume find-new", "<path> <last_gen>\n"
>> - "List the recently modified files in a filesystem."
>> + "List the recently modified files in a filesystem.",
>> + NULL
>> },
>> { do_defrag, -1,
>> "filesystem defragment", "[-vcf] [-s start] [-l len] [-t size] <file>|<dir> [<file>|<dir>...]\n"
>> - "Defragment a file or a directory."
>> + "Defragment a file or a directory.",
>> + "[-vcf] [-s start] [-l len] [-t size] <file>|<dir> [<file>|<dir>...]\n"
>> + "Defragment file data or directory metadata.\n"
>> + "-v be verbose\n"
>> + "-c compress the file while defragmenting\n"
>> + "-f flush data to disk immediately after defragmenting\n"
>> + "-s start defragment only from byte onward\n"
>> + "-l len defragment only up to len bytes\n"
>> + "-t size minimal size of file to be considered for defragmenting\n"
>
> Lots of too long lines.
>
> I don't like to repeat the synopsis passage. How about adding the
> general ->help when printing ->adv_help as well? This reduces the need
> of duplication.
>
> To prove my point, looking at the current version in Hugo's integration
> branch, your two synopsis lines already got inconsistent regarding the
> -c option :-)
>
>> },
>> { do_set_default_subvol, 2,
>> "subvolume set-default", "<id> <path>\n"
>> "Set the subvolume of the filesystem <path> which will be mounted\n"
>> - "as default."
>> + "as default.",
>> + NULL
>> },
>> { do_fssync, 1,
>> "filesystem sync", "<path>\n"
>> - "Force a sync on the filesystem <path>."
>> + "Force a sync on the filesystem <path>.",
>> + NULL
>> },
>> { do_resize, 2,
>> "filesystem resize", "[+/-]<newsize>[gkm]|max <filesystem>\n"
>> "Resize the file system. If 'max' is passed, the filesystem\n"
>> - "will occupe all available space on the device."
>> + "will occupe all available space on the device.",
>> + NULL
>> },
>> { do_show_filesystem, 999,
>> "filesystem show", "[<uuid>|<label>]\n"
>> "Show the info of a btrfs filesystem. If no <uuid> or <label>\n"
>> - "is passed, info of all the btrfs filesystem are shown."
>> + "is passed, info of all the btrfs filesystem are shown.",
>> + NULL
>> },
>> { do_df_filesystem, 1,
>> "filesystem df", "<path>\n"
>> - "Show space usage information for a mount point\n."
>> + "Show space usage information for a mount point.",
>> + NULL
>> },
>> { do_balance, 1,
>> "filesystem balance", "<path>\n"
>> - "Balance the chunks across the device."
>> + "Balance the chunks across the device.",
>> + NULL
>> },
>> { do_scan,
>> 999, "device scan", "[<device> [<device>..]\n"
>> "Scan all device for or the passed device for a btrfs\n"
>> - "filesystem."
>> + "filesystem.",
>> + NULL
>> },
>> { do_add_volume, -2,
>> "device add", "<dev> [<dev>..] <path>\n"
>> - "Add a device to a filesystem."
>> + "Add a device to a filesystem.",
>> + NULL
>> },
>> { do_remove_volume, -2,
>> "device delete", "<dev> [<dev>..] <path>\n"
>> - "Remove a device from a filesystem."
>> + "Remove a device from a filesystem.",
>> + NULL
>> },
>> /* coming soon
>> { 2, "filesystem label", "<label> <path>\n"
>> - "Set the label of a filesystem"
>> + "Set the label of a filesystem",
>> + NULL
>> }
>> */
>> - { 0, 0 , 0 }
>> + { 0, 0, 0, 0 }
>> };
>>
>> static char *get_prgname(char *programname)
>> @@ -128,17 +156,25 @@ static char *get_prgname(char *programname)
>> return np;
>> }
>>
>> -static void print_help(char *programname, struct Command *cmd)
>> +static void print_help(char *programname, struct Command *cmd, int helptype)
>> {
>> char *pc;
>>
>> printf("\t%s %s ", programname, cmd->verb );
>>
>> - for(pc = cmd->help; *pc; pc++){
>> - putchar(*pc);
>> - if(*pc == '\n')
>> - printf("\t\t");
>> - }
>> + if (helptype == ADVANCED_HELP && cmd->adv_help)
>
> As mentioned above, I'd like to have ->help printed here, above. You can
> make the loop in the else branch below unconditional and just put the
> advanced part inside the if.
>
>> + for(pc = cmd->adv_help; *pc; pc++){
>> + putchar(*pc);
>> + if(*pc == '\n')
>> + printf("\t\t");
>> + }
>> + else
>> + for(pc = cmd->help; *pc; pc++){
>> + putchar(*pc);
>> + if(*pc == '\n')
>> + printf("\t\t");
>> + }
>> +
>> putchar('\n');
>> }
>>
>> @@ -148,10 +184,10 @@ static void help(char *np)
>>
>> printf("Usage:\n");
>> for( cp = commands; cp->verb; cp++ )
>> - print_help(np, cp);
>> + print_help(np, cp, BASIC_HELP);
>>
>> printf("\n\t%s help|--help|-h\n\t\tShow the help.\n",np);
> ^^^^^^^^^
> You did not change this, but as we are here, ...
>
>> - printf("\n\t%s <cmd> --help\n\t\tShow detailed help for a command or\n\t\t"
>> + printf("\n\t%s <cmd> --help\n\t\tShow detailed help for a command or"
> ^^^^^^^
> .. why not extending the general rule so that help messages will be
> printed with --help and -h?
>
>> "subset of commands.\n",np);
>> printf("\n%s\n", BTRFS_BUILD_VERSION);
>> }
>> @@ -257,15 +293,14 @@ static int prepare_args(int *ac, char ***av, char *prgname, struct Command *cmd
>>
>>
>> /*
>> -
>> - This function perform the following jobs:
>> + This function performs the following jobs:
>> - show the help if '--help' or 'help' or '-h' are passed
>> - verify that a command is not ambiguous, otherwise show which
>> part of the command is ambiguous
>> - - if after a (even partial) command there is '--help' show the help
>> + - if after a (even partial) command there is '--help' show detailed help
>> for all the matching commands
>> - - if the command doesn't' match show an error
>> - - finally, if a command match, they return which command is matched and
>> + - if the command doesn't match show an error
>> + - finally, if a command matches, they return which command matched and
>> the arguments
>>
>> The function return 0 in case of help is requested; <0 in case
>> @@ -319,7 +354,7 @@ static int parse_args(int argc, char **argv,
>> if(argc>i+1 && !strcmp(argv[i+1],"--help")){
>> if(!helprequested)
>> printf("Usage:\n");
>> - print_help(prgname, cp);
>> + print_help(prgname, cp, ADVANCED_HELP);
>> helprequested=1;
>> continue;
>> }
>
> -Jan
> --
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