jobs.h

   1 /* jobs.h -- structures and definitions used by the jobs.c file. */
   2
   3 /* Copyright (C) 1993-2017 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    Bash is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #if !defined (_JOBS_H_)
  22 #  define _JOBS_H_
  23
  24 #include "quit.h"
  25 #include "siglist.h"
  26
  27 #include "stdc.h"
  28
  29 #include "posixwait.h"
  30
  31 /* Defines controlling the fashion in which jobs are listed. */
  32 #define JLIST_STANDARD       0
  33 #define JLIST_LONG           1
  34 #define JLIST_PID_ONLY       2
  35 #define JLIST_CHANGED_ONLY   3
  36 #define JLIST_NONINTERACTIVE 4
  37
  38 /* I looked it up.  For pretty_print_job ().  The real answer is 24. */
  39 #define LONGEST_SIGNAL_DESC 24
  40
  41 /* Defines for the wait_for functions and for the wait builtin to use */
  42 #define JWAIT_PERROR            0x01
  43 #define JWAIT_FORCE             0x02
  44
  45 /* The max time to sleep while retrying fork() on EAGAIN failure */
  46 #define FORKSLEEP_MAX   16
  47
  48 /* We keep an array of jobs.  Each entry in the array is a linked list
  49    of processes that are piped together.  The first process encountered is
  50    the group leader. */
  51
  52 /* Values for the `running' field of a struct process. */
  53 #define PS_DONE         0
  54 #define PS_RUNNING      1
  55 #define PS_STOPPED      2
  56 #define PS_RECYCLED     4
  57
  58 /* Each child of the shell is remembered in a STRUCT PROCESS.  A circular
  59    chain of such structures is a pipeline. */
  60 typedef struct process {
  61   struct process *next; /* Next process in the pipeline.  A circular chain. */
  62   pid_t pid;            /* Process ID. */
  63   WAIT status;          /* The status of this command as returned by wait. */
  64   int running;          /* Non-zero if this process is running. */
  65   char *command;        /* The particular program that is running. */
  66 } PROCESS;
  67
  68 struct pipeline_saver {
  69   struct process *pipeline;
  70   struct pipeline_saver *next;
  71 };
  72
  73 /* PALIVE really means `not exited' */
  74 #define PSTOPPED(p)     (WIFSTOPPED((p)->status))
  75 #define PRUNNING(p)     ((p)->running == PS_RUNNING)
  76 #define PALIVE(p)       (PRUNNING(p) || PSTOPPED(p))
  77
  78 #define PEXITED(p)      ((p)->running == PS_DONE)
  79 #if defined (RECYCLES_PIDS)
  80 #  define PRECYCLED(p)  ((p)->running == PS_RECYCLED)
  81 #else
  82 #  define PRECYCLED(p)  (0)
  83 #endif
  84 #define PDEADPROC(p)    (PEXITED(p) || PRECYCLED(p))
  85
  86 #define get_job_by_jid(ind)     (jobs[(ind)])
  87
  88 /* A description of a pipeline's state. */
  89 typedef enum { JNONE = -1, JRUNNING = 1, JSTOPPED = 2, JDEAD = 4, JMIXED = 8 } JOB_STATE;
  90 #define JOBSTATE(job)   (jobs[(job)]->state)
  91 #define J_JOBSTATE(j)   ((j)->state)
  92
  93 #define STOPPED(j)      (jobs[(j)]->state == JSTOPPED)
  94 #define RUNNING(j)      (jobs[(j)]->state == JRUNNING)
  95 #define DEADJOB(j)      (jobs[(j)]->state == JDEAD)
  96
  97 #define INVALID_JOB(j)  ((j) < 0 || (j) >= js.j_jobslots || get_job_by_jid(j) == 0)
  98
  99 /* Values for the FLAGS field in the JOB struct below. */
 100 #define J_FOREGROUND 0x01 /* Non-zero if this is running in the foreground.  */
 101 #define J_NOTIFIED   0x02 /* Non-zero if already notified about job state.   */
 102 #define J_JOBCONTROL 0x04 /* Non-zero if this job started under job control. */
 103 #define J_NOHUP      0x08 /* Don't send SIGHUP to job if shell gets SIGHUP. */
 104 #define J_STATSAVED  0x10 /* A process in this job had had status saved via $! */
 105 #define J_ASYNC      0x20 /* Job was started asynchronously */
 106 #define J_PIPEFAIL   0x40 /* pipefail set when job was started */
 107
 108 #define IS_FOREGROUND(j)        ((jobs[j]->flags & J_FOREGROUND) != 0)
 109 #define IS_NOTIFIED(j)          ((jobs[j]->flags & J_NOTIFIED) != 0)
 110 #define IS_JOBCONTROL(j)        ((jobs[j]->flags & J_JOBCONTROL) != 0)
 111 #define IS_ASYNC(j)             ((jobs[j]->flags & J_ASYNC) != 0)
 112
 113 typedef struct job {
 114   char *wd;        /* The working directory at time of invocation. */
 115   PROCESS *pipe;   /* The pipeline of processes that make up this job. */
 116   pid_t pgrp;      /* The process ID of the process group (necessary). */
 117   JOB_STATE state; /* The state that this job is in. */
 118   int flags;       /* Flags word: J_NOTIFIED, J_FOREGROUND, or J_JOBCONTROL. */
 119 #if defined (JOB_CONTROL)
 120   COMMAND *deferred;    /* Commands that will execute when this job is done. */
 121   sh_vptrfunc_t *j_cleanup; /* Cleanup function to call when job marked JDEAD */
 122   PTR_T cleanarg;       /* Argument passed to (*j_cleanup)() */
 123 #endif /* JOB_CONTROL */
 124 } JOB;
 125
 126 struct jobstats {
 127   /* limits */
 128   long c_childmax;
 129   /* child process statistics */
 130   int c_living;         /* running or stopped child processes */
 131   int c_reaped;         /* exited child processes still in jobs list */
 132   int c_injobs;         /* total number of child processes in jobs list */
 133   /* child process totals */
 134   int c_totforked;      /* total number of children this shell has forked */
 135   int c_totreaped;      /* total number of children this shell has reaped */
 136   /* job counters and indices */
 137   int j_jobslots;       /* total size of jobs array */
 138   int j_lastj;          /* last (newest) job allocated */
 139   int j_firstj;         /* first (oldest) job allocated */
 140   int j_njobs;          /* number of non-NULL jobs in jobs array */
 141   int j_ndead;          /* number of JDEAD jobs in jobs array */
 142   /* */
 143   int j_current;        /* current job */
 144   int j_previous;       /* previous job */
 145   /* */
 146   JOB *j_lastmade;      /* last job allocated by stop_pipeline */
 147   JOB *j_lastasync;     /* last async job allocated by stop_pipeline */
 148 };
 149
 150 /* Revised to accommodate new hash table bgpids implementation. */
 151 typedef pid_t ps_index_t;
 152
 153 struct pidstat {
 154   ps_index_t bucket_next;
 155   ps_index_t bucket_prev;
 156
 157   pid_t pid;
 158   bits16_t status;              /* only 8 bits really needed */
 159 };
 160
 161 struct bgpids {
 162   struct pidstat *storage;      /* storage arena */
 163
 164   ps_index_t head;
 165   ps_index_t nalloc;
 166
 167   int npid;
 168 };
 169
 170 #define NO_PIDSTAT (ps_index_t)-1
 171
 172 #define NO_JOB  -1      /* An impossible job array index. */
 173 #define DUP_JOB -2      /* A possible return value for get_job_spec (). */
 174 #define BAD_JOBSPEC -3  /* Bad syntax for job spec. */
 175
 176 /* A value which cannot be a process ID. */
 177 #define NO_PID (pid_t)-1
 178
 179 #define ANY_PID (pid_t)-1
 180
 181 /* System calls. */
 182 #if !defined (HAVE_UNISTD_H)
 183 extern pid_t fork (), getpid (), getpgrp ();
 184 #endif /* !HAVE_UNISTD_H */
 185
 186 /* Stuff from the jobs.c file. */
 187 extern struct jobstats js;
 188
 189 extern pid_t original_pgrp, shell_pgrp, pipeline_pgrp;
 190 extern volatile pid_t last_made_pid, last_asynchronous_pid;
 191 extern int asynchronous_notification;
 192
 193 extern int already_making_children;
 194 extern int running_in_background;
 195
 196 extern PROCESS *last_procsub_child;
 197
 198 extern JOB **jobs;
 199
 200 extern void making_children __P((void));
 201 extern void stop_making_children __P((void));
 202 extern void cleanup_the_pipeline __P((void));
 203 extern void discard_last_procsub_child __P((void));
 204 extern void save_pipeline __P((int));
 205 extern PROCESS *restore_pipeline __P((int));
 206 extern void start_pipeline __P((void));
 207 extern int stop_pipeline __P((int, COMMAND *));
 208 extern int discard_pipeline __P((PROCESS *));
 209 extern void append_process __P((char *, pid_t, int, int));
 210
 211 extern void delete_job __P((int, int));
 212 extern void nohup_job __P((int));
 213 extern void delete_all_jobs __P((int));
 214 extern void nohup_all_jobs __P((int));
 215
 216 extern int count_all_jobs __P((void));
 217
 218 extern void terminate_current_pipeline __P((void));
 219 extern void terminate_stopped_jobs __P((void));
 220 extern void hangup_all_jobs __P((void));
 221 extern void kill_current_pipeline __P((void));
 222
 223 #if defined (__STDC__) && defined (pid_t)
 224 extern int get_job_by_pid __P((int, int));
 225 extern void describe_pid __P((int));
 226 #else
 227 extern int get_job_by_pid __P((pid_t, int));
 228 extern void describe_pid __P((pid_t));
 229 #endif
 230
 231 extern void list_one_job __P((JOB *, int, int, int));
 232 extern void list_all_jobs __P((int));
 233 extern void list_stopped_jobs __P((int));
 234 extern void list_running_jobs __P((int));
 235
 236 extern pid_t make_child __P((char *, int));
 237
 238 extern int get_tty_state __P((void));
 239 extern int set_tty_state __P((void));
 240
 241 extern int job_exit_status __P((int));
 242 extern int job_exit_signal __P((int));
 243
 244 extern int wait_for_single_pid __P((pid_t, int));
 245 extern void wait_for_background_pids __P((void));
 246 extern int wait_for __P((pid_t));
 247 extern int wait_for_job __P((int, int));
 248 extern int wait_for_any_job __P((int));
 249
 250 extern void wait_sigint_cleanup __P((void));
 251
 252 extern void notify_and_cleanup __P((void));
 253 extern void reap_dead_jobs __P((void));
 254 extern int start_job __P((int, int));
 255 extern int kill_pid __P((pid_t, int, int));
 256 extern int initialize_job_control __P((int));
 257 extern void initialize_job_signals __P((void));
 258 extern int give_terminal_to __P((pid_t, int));
 259
 260 extern void run_sigchld_trap __P((int));
 261
 262 extern int freeze_jobs_list __P((void));
 263 extern void unfreeze_jobs_list __P((void));
 264 extern void set_jobs_list_frozen __P((int));
 265 extern int set_job_control __P((int));
 266 extern void without_job_control __P((void));
 267 extern void end_job_control __P((void));
 268 extern void restart_job_control __P((void));
 269 extern void set_sigchld_handler __P((void));
 270 extern void ignore_tty_job_signals __P((void));
 271 extern void default_tty_job_signals __P((void));
 272 extern void get_original_tty_job_signals __P((void));
 273
 274 extern void init_job_stats __P((void));
 275
 276 extern void close_pgrp_pipe __P((void));
 277 extern void save_pgrp_pipe __P((int *, int));
 278 extern void restore_pgrp_pipe __P((int *));
 279
 280 extern void set_maxchild __P((int));
 281
 282 extern int job_control;         /* set to 0 in nojobs.c */
 283
 284 #endif /* _JOBS_H_ */