src/pop3/pop3-client.h

#ifndef POP3_CLIENT_H
#define POP3_CLIENT_H

#include "seq-range-array.h"

struct client;
struct mail_storage;
struct mail_storage_service_ctx;

typedef void command_func_t(struct client *client);

#define MSGS_BITMASK_SIZE(client) \
    (MALLOC_ADD((client)->messages_count, (CHAR_BIT-1)) / CHAR_BIT)

/* Stop reading input when output buffer has this many bytes. Once the buffer
   size has dropped to half of it, start reading input again. */
#define POP3_OUTBUF_THROTTLE_SIZE 4096

#define POP3_CLIENT_OUTPUT_FULL(client) \
    (o_stream_get_buffer_used_size((client)->output) >= POP3_OUTBUF_THROTTLE_SIZE)

struct pop3_client_vfuncs {
    void (*destroy)(struct client *client, const char *reason);

};

/*
   pop3_msn = 1..n in the POP3 protocol
   msgnum = 0..n-1 = pop3_msn-1
   seq = 1..n = mail's sequence number in lib-storage. when pop3 sort ordering
     is used, msgnum_to_seq_map[] can be used for translation.
*/
struct client {
    struct client *prev, *next;

    struct pop3_client_vfuncs v;
    const char *session_id;

    int fd_in, fd_out;
    struct io *io;
    struct istream *input;
    struct ostream *output;
    struct timeout *to_idle, *to_commit;

    command_func_t *cmd;
    void *cmd_context;

    pool_t pool;
    struct mail_storage_service_user *service_user;
    struct mail_user *user;
    struct mail_namespace *inbox_ns;
    struct mailbox *mailbox;
    struct mailbox_transaction_context *trans;
    struct mail_keywords *deleted_kw;

    struct timeout *to_session_dotlock_refresh;
    struct dotlock *session_dotlock;

    time_t last_input, last_output;
    unsigned int bad_counter;
    unsigned int highest_expunged_fetch_msgnum;

    unsigned int uid_validity;
    unsigned int messages_count;
    unsigned int deleted_count, seen_change_count;
    uoff_t total_size;
    uoff_t deleted_size;
    uint32_t last_seen_pop3_msn, lowest_retr_pop3_msn;

    /* All sequences currently visible in the mailbox. */
    ARRAY_TYPE(seq_range) all_seqs;
    uint32_t highest_seq;

    /* [msgnum] contains mail seq. anything after it has seq = msgnum+1 */
    uint32_t *msgnum_to_seq_map;
    uint32_t msgnum_to_seq_map_count;

    uoff_t top_bytes;
    uoff_t retr_bytes;
    unsigned int top_count;
    unsigned int retr_count;

    /* [msgnum] */
    const char **message_uidls;
    uoff_t *message_sizes;
    /* [msgnum/8] & msgnum%8 */
    unsigned char *deleted_bitmask;
    unsigned char *seen_bitmask;

    /* settings: */
    const struct pop3_settings *set;
    const struct mail_storage_settings *mail_set;
    pool_t uidl_pool;
    enum uidl_keys uidl_keymask;

    /* Module-specific contexts. */
    ARRAY(union pop3_module_context *) module_contexts;

    bool destroyed:1;
    bool disconnected:1;
    bool deleted:1;
    bool waiting_input:1;
    bool anvil_sent:1;
    bool message_uidls_save:1;
    bool delete_success:1;
};

struct pop3_module_register {
    unsigned int id;
};

union pop3_module_context {
    struct pop3_client_vfuncs super;
    struct pop3_module_register *reg;
};
extern struct pop3_module_register pop3_module_register;

extern struct client *pop3_clients;
extern unsigned int pop3_client_count;

/* Create new client with specified input/output handles. socket specifies
   if the handle is a socket. */
struct client *client_create(int fd_in, int fd_out, const char *session_id,
                 struct mail_user *user,
                 struct mail_storage_service_user *service_user,
                 const struct pop3_settings *set);
int client_init_mailbox(struct client *client, const char **error_r);
void client_destroy(struct client *client, const char *reason) ATTR_NULL(2);

/* Disconnect client connection */
void client_disconnect(struct client *client, const char *reason);

/* Send a line of data to client */
void client_send_line(struct client *client, const char *fmt, ...)
    ATTR_FORMAT(2, 3);
void client_send_storage_error(struct client *client);

bool client_handle_input(struct client *client);
bool client_update_mails(struct client *client);

void clients_destroy_all(void);

int pop3_lock_session(struct client *client);

#endif