#include <X11/Xlib.h>
#include "bsdtimespec.h"
-#include "khatus_lib_log.h"
-#include "khatus_lib_time.h"
+#include "khlib_log.h"
+#include "khlib_time.h"
-#define usage(...) {print_usage(); fprintf(stderr, "Error:\n " __VA_ARGS__); exit(EXIT_FAILURE);}
+#define usage(...) { \
+ print_usage(); \
+ fprintf(stderr, "Error:\n " __VA_ARGS__); \
+ exit(EXIT_FAILURE); \
+}
#define ERRMSG "ERROR"
+
static const char errmsg[] = ERRMSG;
static const int errlen = sizeof(ERRMSG) - 1;
char *argv0;
-/* TODO: Convert fifo list to fifo array. */
-typedef struct Fifo Fifo;
-struct Fifo {
- char *name;
- int fd;
- int width;
- int last_read;
- int ttl;
- int pos_init; /* Initial position on the output buffer. */
- int pos_curr; /* Current position on the output buffer. */
- int pos_final; /* Final position on the output buffer. */
- Fifo *next;
+/* TODO: Convert slot list to slot array. */
+typedef struct Slot Slot;
+struct Slot {
+ char *in_fifo;
+ int in_fd;
+ struct timespec in_last_read;
+ struct timespec out_ttl;
+ int out_width;
+ int out_pos_lo; /* Lowest position on the output buffer. */
+ int out_pos_cur; /* Current position on the output buffer. */
+ int out_pos_hi; /* Highest position on the output buffer. */
+ Slot *next;
};
typedef struct Config Config;
struct Config {
double interval;
char * separator;
- Fifo * fifos;
- int fifo_count;
+ Slot * slots;
+ int slot_count;
int total_width;
int output_to_x_root_window;
-} defaults = {
- .interval = 1.0,
- .separator = "|",
- .fifos = NULL,
- .fifo_count = 0,
- .total_width = 0,
- .output_to_x_root_window = 0,
};
enum read_status {
FAILURE
};
+Slot *
+slots_rev(Slot *old)
+{
+ Slot *tmp = NULL;
+ Slot *new = NULL;
+
+ while (old) {
+ tmp = old->next;
+ old->next = new;
+ new = old;
+ old = tmp;
+ }
+ return new;
+}
+
void
-fifo_print_one(Fifo *f)
+slot_print(Slot *s)
{
- info("Fifo "
+ khlib_info("Slot "
"{"
- " name = %s,"
- " fd = %d,"
- " width = %d,"
- " last_read = %d,"
- " ttl = %d,"
- " pos_init = %d,"
- " pos_curr = %d,"
- " pos_final = %d,"
+ " in_fifo = %s,"
+ " in_fd = %d,"
+ " out_width = %d,"
+ " in_last_read = {tv_sec = %ld, tv_nsec = %ld}"
+ " out_ttl = {tv_sec = %ld, tv_nsec = %ld},"
+ " out_pos_lo = %d,"
+ " out_pos_cur = %d,"
+ " out_pos_hi = %d,"
" next = %p,"
" }\n",
- f->name,
- f->fd,
- f->width,
- f->last_read,
- f->ttl,
- f->pos_init,
- f->pos_curr,
- f->pos_final,
- f->next
+ s->in_fifo,
+ s->in_fd,
+ s->out_width,
+ s->in_last_read.tv_sec,
+ s->in_last_read.tv_nsec,
+ s->out_ttl.tv_sec,
+ s->out_ttl.tv_nsec,
+ s->out_pos_lo,
+ s->out_pos_cur,
+ s->out_pos_hi,
+ s->next
);
}
void
-fifo_print_all(Fifo *head)
+slots_print(Slot *head)
{
- for (Fifo *f = head; f; f = f->next) {
- fifo_print_one(f);
+ for (Slot *s = head; s; s = s->next) {
+ slot_print(s);
+ }
+}
+
+void
+slot_expire(Slot *s, struct timespec t, char *buf)
+{
+ struct timespec td;
+
+ timespecsub(&t, &(s->in_last_read), &td);
+ if (timespeccmp(&td, &(s->out_ttl), >=)) {
+ /* TODO: Maybe configurable expiry character. */
+ memset(buf + s->out_pos_lo, '_', s->out_pos_hi - s->out_pos_lo);
+ khlib_warn("Slot expired: \"%s\"\n", s->in_fifo);
+ }
+}
+
+void
+slot_read_error(Slot *s, char *buf)
+{
+ char *b;
+ int i;
+
+ b = buf + s->out_pos_lo;
+ /* Copy as much of the error message as possible.
+ * EXCLUDING the terminating \0. */
+ for (i = 0; i < errlen && i < s->out_width; i++)
+ b[i] = errmsg[i];
+ /* Any remaining positions: */
+ for (; i < s->out_width; i++)
+ b[i] = '_';
+}
+
+enum read_status
+slot_read(Slot *s, struct timespec t, char *buf)
+{
+ char c; /* Character read. */
+ int r; /* Remaining unused positions in buffer range. */
+
+ for (;;) {
+ switch (read(s->in_fd, &c, 1)) {
+ case -1:
+ khlib_error(
+ "Failed to read: \"%s\". errno: %d, msg: %s\n",
+ s->in_fifo,
+ errno,
+ strerror(errno)
+ );
+ switch (errno) {
+ case EINTR:
+ case EAGAIN:
+ return RETRY;
+ default:
+ return FAILURE;
+ }
+ case 0:
+ khlib_debug("%s: End of FILE\n", s->in_fifo);
+ s->out_pos_cur = s->out_pos_lo;
+ return END_OF_FILE;
+ case 1:
+ /* TODO: Consider making msg term char a CLI option */
+ if (c == '\n' || c == '\0') {
+ r = s->out_pos_hi - s->out_pos_cur;
+ if (r > 0)
+ memset(buf + s->out_pos_cur, ' ', r);
+ s->out_pos_cur = s->out_pos_lo;
+ s->in_last_read = t;
+ return END_OF_MESSAGE;
+ } else {
+ if (s->out_pos_cur <= s->out_pos_hi)
+ buf[s->out_pos_cur++] = c;
+ /* Drop beyond available range. */
+ /*
+ * TODO Define max after which we stop reading.
+ * To ensure that a rogue large message
+ * doesn't trap us here.
+ */
+ }
+ break;
+ default:
+ assert(0);
+ }
}
}
+void
+slots_read(Config *cfg, struct timespec *ti, char *buf)
+{
+ fd_set fds;
+ int maxfd = -1;
+ int ready = 0;
+ struct stat st;
+ struct timespec t;
+ Slot *s;
+
+ FD_ZERO(&fds);
+ for (s = cfg->slots; s; s = s->next) {
+ /* TODO: Create the FIFO if it doesn't already exist. */
+ if (lstat(s->in_fifo, &st) < 0) {
+ khlib_error(
+ "Cannot stat \"%s\". Error: %s\n",
+ s->in_fifo,
+ strerror(errno)
+ );
+ slot_read_error(s, buf);
+ continue;
+ }
+ if (!(st.st_mode & S_IFIFO)) {
+ khlib_error("\"%s\" is not a FIFO\n", s->in_fifo);
+ slot_read_error(s, buf);
+ continue;
+ }
+ if (s->in_fd < 0) {
+ khlib_debug(
+ "%s: closed. opening. in_fd: %d\n",
+ s->in_fifo,
+ s->in_fd
+ );
+ s->in_fd = open(s->in_fifo, O_RDONLY | O_NONBLOCK);
+ } else {
+ khlib_debug(
+ "%s: already openned. in_fd: %d\n",
+ s->in_fifo,
+ s->in_fd
+ );
+ }
+ if (s->in_fd == -1) {
+ /* TODO Consider backing off retries for failed slots */
+ khlib_error("Failed to open \"%s\"\n", s->in_fifo);
+ slot_read_error(s, buf);
+ continue;
+ }
+ khlib_debug("%s: open. in_fd: %d\n", s->in_fifo, s->in_fd);
+ if (s->in_fd > maxfd)
+ maxfd = s->in_fd;
+ FD_SET(s->in_fd, &fds);
+ }
+ khlib_debug("selecting...\n");
+ ready = pselect(maxfd + 1, &fds, NULL, NULL, ti, NULL);
+ khlib_debug("ready: %d\n", ready);
+ clock_gettime(CLOCK_MONOTONIC, &t);
+ if (ready == -1) {
+ switch (errno) {
+ case EINTR:
+ khlib_error(
+ "pselect temp failure: %d, errno: %d, msg: %s\n",
+ ready,
+ errno,
+ strerror(errno)
+ );
+ /* TODO: Reconsider what to do here. */
+ return;
+ default:
+ khlib_fatal(
+ "pselect failed: %d, errno: %d, msg: %s\n",
+ ready,
+ errno,
+ strerror(errno)
+ );
+ }
+ }
+ /* At-least-once ensures that expiries are still checked on timeouts. */
+ do {
+ for (s = cfg->slots; s; s = s->next) {
+ if (FD_ISSET(s->in_fd, &fds)) {
+ khlib_debug("reading: %s\n", s->in_fifo);
+ switch (slot_read(s, t, buf)) {
+ /*
+ * ### MESSAGE LOSS ###
+ * is introduced by closing at EOM in addition
+ * to EOF, since there may be unread messages
+ * remaining in the pipe. However,
+ *
+ * ### INTER-MESSAGE PUSHBACK ###
+ * is also gained, since pipes block at the
+ * "open" call.
+ *
+ * This is an acceptable trade-off because we
+ * are a stateless reporter of a _most-recent_
+ * status, not a stateful accumulator.
+ */
+ case END_OF_MESSAGE:
+ case END_OF_FILE:
+ case FAILURE:
+ close(s->in_fd);
+ s->in_fd = -1;
+ ready--;
+ break;
+ case RETRY:
+ break;
+ default:
+ assert(0);
+ }
+ } else {
+ slot_expire(s, t, buf);
+ }
+ }
+ } while (ready);
+ assert(ready == 0);
+}
+
void
config_print(Config *cfg)
{
- info(
+ khlib_info(
"Config "
"{"
" interval = %f,"
" separator = %s,"
- " fifo_count = %d,"
+ " slot_count = %d,"
" total_width = %d,"
- " fifos = ..."
+ " slots = ..."
" }\n",
cfg->interval,
cfg->separator,
- cfg->fifo_count,
+ cfg->slot_count,
cfg->total_width
);
- fifo_print_all(cfg->fifos);
+ slots_print(cfg->slots);
}
int
-is_pos_num(char *s)
+is_pos_num(char *str)
{
- while (*s != '\0')
- if (!isdigit(*(s++)))
+ while (*str != '\0')
+ if (!isdigit(*(str++)))
return 0;
return 1;
}
int
-is_decimal(char *s)
+is_decimal(char *str)
{
char c;
int seen = 0;
- while ((c = *(s++)) != '\0')
+ while ((c = *(str++)) != '\0')
if (!isdigit(c)) {
if (c == '.' && !seen++)
continue;
" SPEC = FILE_PATH DATA_WIDTH DATA_TTL\n"
" FILE_PATH = string\n"
" DATA_WIDTH = int (* (positive) number of characters *)\n"
- " DATA_TTL = int (* (positive) number of seconds *)\n"
+ " DATA_TTL = float (* (positive) number of seconds *)\n"
" OPTION = -i INTERVAL\n"
" | -s SEPARATOR\n"
" | -x (* Output to X root window *)\n"
" | -l LOG_LEVEL\n"
" SEPARATOR = string\n"
- " INTERVAL = int (* (positive) number of seconds *)\n"
+ " INTERVAL = float (* (positive) number of seconds *)\n"
" LOG_LEVEL = int (* %d through %d *)\n"
"\n",
argv0,
);
}
-void opts_parse_any(Config *, int, char *[], int); /* For mutually-recursive calls. */
+/* For mutually-recursive calls. */
+void opts_parse_any(Config *, int, char *[], int);
void
parse_opts_opt_i(Config *cfg, int argc, char *argv[], int i)
usage("Option -l parameter is invalid: \"%s\"\n", param);
log_level = atoi(param);
if (log_level > Debug)
- usage("Option -l value (%d) exceeds maximum (%d)\n", log_level, Debug);
- _khatus_lib_log_level = log_level;
+ usage(
+ "Option -l value (%d) exceeds maximum (%d)\n",
+ log_level,
+ Debug
+ );
+ _khlib_log_level = log_level;
opts_parse_any(cfg, argc, argv, i);
}
void
parse_opts_spec(Config *cfg, int argc, char *argv[], int i)
{
+ char *n;
+ char *w;
+ char *t;
+ struct timespec in_last_read;
+ Slot *s;
+
if ((i + 3) > argc)
- usage("[spec] Parameter(s) missing for fifo \"%s\".\n", argv[i]);
+ usage(
+ "[spec] Parameter(s) missing for fifo \"%s\".\n",
+ argv[i]
+ );
- char *n = argv[i++];
- char *w = argv[i++];
- char *t = argv[i++];
+ n = argv[i++];
+ w = argv[i++];
+ t = argv[i++];
if (!is_pos_num(w))
usage("[spec] Invalid width: \"%s\", for fifo \"%s\"\n", w, n);
- if (!is_pos_num(t))
+ if (!is_decimal(t))
usage("[spec] Invalid TTL: \"%s\", for fifo \"%s\"\n", t, n);
- Fifo *f = calloc(1, sizeof(struct Fifo));
- if (f) {
- f->name = n;
- f->fd = -1;
- f->width = atoi(w);
- f->ttl = atoi(t);
- f->last_read = 0;
- f->pos_init = cfg->total_width;
- f->pos_curr = f->pos_init;
- f->pos_final = f->pos_init + f->width - 1;
- f->next = cfg->fifos;
-
- cfg->fifos = f;
- cfg->total_width += f->width;
- cfg->fifo_count++;
+
+ in_last_read.tv_sec = 0;
+ in_last_read.tv_nsec = 0;
+ s = calloc(1, sizeof(struct Slot));
+
+ if (s) {
+ s->in_fifo = n;
+ s->in_fd = -1;
+ s->out_width = atoi(w);
+ s->out_ttl = khlib_timespec_of_float(atof(t));
+ s->in_last_read = in_last_read;
+ s->out_pos_lo = cfg->total_width;
+ s->out_pos_cur = s->out_pos_lo;
+ s->out_pos_hi = s->out_pos_lo + s->out_width - 1;
+ s->next = cfg->slots;
+
+ cfg->slots = s;
+ cfg->total_width += s->out_width;
+ cfg->slot_count++;
} else {
- fatal("[memory] Allocation failure.");
+ khlib_fatal("[memory] Allocation failure.");
}
opts_parse_any(cfg, argc, argv, i);
}
opts_parse(Config *cfg, int argc, char *argv[])
{
opts_parse_any(cfg, argc, argv, 1);
-
- Fifo *last = cfg->fifos;
- cfg->fifos = NULL;
- for (Fifo *f = last; f; ) {
- Fifo *next = f->next;
- f->next = cfg->fifos;
- cfg->fifos = f;
- f = next;
- }
-}
-
-void
-fifo_read_error(Fifo *f, char *buf)
-{
- char *b;
- int i;
-
- b = buf + f->pos_init;
- /* Copy as much of the error message as possible.
- * EXCLUDING the reminating \0. */
- for (i = 0; i < errlen && i < f->width; i++)
- b[i] = errmsg[i];
- /* Any remaining slots: */
- for (; i < f->width; i++)
- b[i] = '_';
-}
-
-enum read_status
-fifo_read_one(Fifo *f, char *buf)
-{
- /* Initialize all to an impossible value: */
- ssize_t n = -5; /* Number of bytes read. */
- char c = -1; /* Character read. */
- int r = -1; /* Remaining unused slots in buffer range. */
-
- for (;;) {
- n = read(f->fd, &c, 1);
- assert(n >= -1 && n <= 1);
- switch (n) {
- case -1:
- error("Failed to read: \"%s\". errno: %d, msg: %s\n",
- f->name, errno, strerror(errno));
- switch (errno) {
- case EINTR:
- case EAGAIN:
- return RETRY;
- default:
- return FAILURE;
- }
- case 0:
- debug("%s: End of FILE\n", f->name);
- f->pos_curr = f->pos_init;
- return END_OF_FILE;
- case 1:
- /* TODO: Consider making msg term char a CLI option */
- if (c == '\n' || c == '\0') {
- r = f->pos_final - f->pos_curr;
- if (r > 0)
- memset(buf + f->pos_curr, ' ', r);
- f->pos_curr = f->pos_init;
- return END_OF_MESSAGE;
- } else {
- if (f->pos_curr <= f->pos_final)
- buf[f->pos_curr++] = c;
- /* Drop beyond available range. */
- }
- break;
- default:
- assert(0);
- }
- }
- /* TODO Record timestamp read */
-}
-
-void
-fifo_read_all(Config *cfg, char *buf)
-{
- fd_set fds;
- int maxfd = -1;
- int ready;
- struct stat st;
-
- FD_ZERO(&fds);
- for (Fifo *f = cfg->fifos; f; f = f->next) {
- /* TODO: Create the FIFO if it doesn't already exist. */
- if (lstat(f->name, &st) < 0) {
- error("Cannot stat \"%s\". Error: %s\n", f->name, strerror(errno));
- fifo_read_error(f, buf);
- continue;
- }
- if (!(st.st_mode & S_IFIFO)) {
- error("\"%s\" is not a FIFO\n", f->name);
- fifo_read_error(f, buf);
- continue;
- }
- if (f->fd < 0) {
- debug("%s: closed. opening. fd: %d\n", f->name, f->fd);
- f->fd = open(f->name, O_RDONLY | O_NONBLOCK);
- } else {
- debug("%s: already openned. fd: %d\n", f->name, f->fd);
- }
- if (f->fd == -1) {
- /* TODO: Consider backing off retries for failed fifos. */
- error("Failed to open \"%s\"\n", f->name);
- fifo_read_error(f, buf);
- continue;
- }
- debug("%s: open. fd: %d\n", f->name, f->fd);
- if (f->fd > maxfd)
- maxfd = f->fd;
- FD_SET(f->fd, &fds);
- }
- debug("selecting...\n");
- ready = select(maxfd + 1, &fds, NULL, NULL, NULL);
- debug("ready: %d\n", ready);
- assert(ready != 0);
- if (ready < 0)
- fatal("%s", strerror(errno));
- for (Fifo *f = cfg->fifos; f; f = f->next) {
- if (FD_ISSET(f->fd, &fds)) {
- debug("reading: %s\n", f->name);
- switch (fifo_read_one(f, buf)) {
- case END_OF_FILE:
- case FAILURE:
- close(f->fd);
- f->fd = -1;
- break;
- case END_OF_MESSAGE:
- case RETRY:
- break;
- default:
- assert(0);
- }
- }
- }
+ cfg->slots = slots_rev(cfg->slots);
}
int
main(int argc, char *argv[])
{
+ Config cfg = {
+ .interval = 1.0,
+ .separator = "|",
+ .slots = NULL,
+ .slot_count = 0,
+ .total_width = 0,
+ .output_to_x_root_window = 0,
+ };
+
int width = 0;
- int nfifos = 0;
+ int nslots = 0;
int seplen = 0;
int prefix = 0;
int errors = 0;
char *buf;
- Config cfg0 = defaults;
- Config *cfg = &cfg0;
- Display *display = NULL;
+ Display *d = NULL;
struct stat st;
struct timespec
- t0, /* time stamp. before reading fifos */
- t1, /* time stamp. after reading fifos */
+ t0, /* time stamp. before reading slots */
+ t1, /* time stamp. after reading slots */
ti, /* time interval desired (t1 - t0) */
td, /* time interval measured (t1 - t0) */
tc; /* time interval correction (ti - td) when td < ti */
+ Slot *s;
argv0 = argv[0];
- opts_parse(cfg, argc, argv);
- debug("argv0 = %s\n", argv0);
- config_print(cfg);
+ opts_parse(&cfg, argc, argv);
+ khlib_debug("argv0 = %s\n", argv0);
+ config_print(&cfg);
- ti = timespec_of_float(cfg->interval);
+ ti = khlib_timespec_of_float(cfg.interval);
- if (cfg->fifos == NULL)
- usage("No fifo specs were given!\n");
+ if (cfg.slots == NULL)
+ usage("No slot specs were given!\n");
/* 1st pass to check file existence and type */
- for (Fifo *f = cfg->fifos; f; f = f->next) {
- if (lstat(f->name, &st) < 0) {
- error("Cannot stat \"%s\". Error: %s\n", f->name, strerror(errno));
+ for (s = cfg.slots; s; s = s->next) {
+ if (lstat(s->in_fifo, &st) < 0) {
+ khlib_error(
+ "Cannot stat \"%s\". Error: %s\n",
+ s->in_fifo,
+ strerror(errno)
+ );
errors++;
continue;
}
if (!(st.st_mode & S_IFIFO)) {
- error("\"%s\" is not a FIFO\n", f->name);
+ khlib_error("\"%s\" is not a FIFO\n", s->in_fifo);
errors++;
continue;
}
}
if (errors)
- fatal("Encountered errors with the given file paths. See log.\n");
+ khlib_fatal(
+ "Encountered errors with given file paths. See log.\n"
+ );
- width = cfg->total_width;
- seplen = strlen(cfg->separator);
+ width = cfg.total_width;
+ seplen = strlen(cfg.separator);
/* 2nd pass to make space for separators */
- for (Fifo *f = cfg->fifos; f; f = f->next) {
- f->pos_init += prefix;
- f->pos_final += prefix;
- f->pos_curr = f->pos_init;
+ for (s = cfg.slots; s; s = s->next) {
+ s->out_pos_lo += prefix;
+ s->out_pos_hi += prefix;
+ s->out_pos_cur = s->out_pos_lo;
prefix += seplen;
- nfifos++;
+ nslots++;
}
- width += (seplen * (nfifos - 1));
+ width += (seplen * (nslots - 1));
buf = calloc(1, width + 1);
if (buf == NULL)
- fatal("[memory] Failed to allocate buffer of %d bytes", width);
+ khlib_fatal(
+ "[memory] Failed to allocate buffer of %d bytes",
+ width
+ );
memset(buf, ' ', width);
buf[width] = '\0';
/* 3rd pass to set the separators */
- for (Fifo *f = cfg->fifos; f; f = f->next) {
- if (f->pos_init) { /* Skip the first, left-most */
+ for (s = cfg.slots; s; s = s->next) {
+ if (s->out_pos_lo) { /* Skip the first, left-most */
/* Copying only seplen ensures we omit the '\0' byte. */
- strncpy(buf + (f->pos_init - seplen), cfg->separator, seplen);
+ strncpy(
+ buf + (s->out_pos_lo - seplen),
+ cfg.separator,
+ seplen
+ );
}
}
- if (cfg->output_to_x_root_window && !(display = XOpenDisplay(NULL)))
- fatal("XOpenDisplay failed with: %p\n", display);
+ if (cfg.output_to_x_root_window && !(d = XOpenDisplay(NULL)))
+ khlib_fatal("XOpenDisplay failed with: %p\n", d);
/* TODO: Handle signals */
for (;;) {
clock_gettime(CLOCK_MONOTONIC, &t0); // FIXME: check errors
- /* TODO: Cache expiration. i.e. use the TTL */
- /* TODO: How to trigger TTL check? On select? Alarm signal? */
- /* TODO: Set timeout on fifo_read_all based on diff of last time of
- * fifo_read_all and desired time of next TTL check.
- */
- /* TODO: How long to wait on IO? Max TTL? */
- fifo_read_all(cfg, buf);
- if (cfg->output_to_x_root_window) {
- if (XStoreName(display, DefaultRootWindow(display), buf) < 0)
- fatal("XStoreName failed.\n");
- XFlush(display);
+ slots_read(&cfg, &ti, buf);
+ if (cfg.output_to_x_root_window) {
+ if (XStoreName(d, DefaultRootWindow(d), buf) < 0)
+ khlib_fatal("XStoreName failed.\n");
+ XFlush(d);
} else {
puts(buf);
fflush(stdout);
}
clock_gettime(CLOCK_MONOTONIC, &t1); // FIXME: check errors
timespecsub(&t1, &t0, &td);
- debug("td {tv_sec = %ld, tv_nsec = %ld}\n", td.tv_sec, td.tv_nsec);
+ khlib_debug(
+ "td {tv_sec = %ld, tv_nsec = %ld}\n",
+ td.tv_sec,
+ td.tv_nsec
+ );
if (timespeccmp(&td, &ti, <)) {
- /* Pushback on data producers by refusing to read the
+ /*
+ * Pushback on data producers by refusing to read the
* pipe more frequently than the interval.
*/
timespecsub(&ti, &td, &tc);
- debug("snooze YES\n");
- snooze(&tc);
- } else {
- debug("snooze NO\n");
+ khlib_sleep(&tc);
}
}
-
return EXIT_SUCCESS;
}