git.scottworley.com Git - tl-append/blob - tl-append-test.c

   1 #define _POSIX_C_SOURCE 2
   2 #define _XOPEN_SOURCE
   3 #define _GNU_SOURCE
   4 #include <assert.h>
   5 #include <ctype.h>
   6 #include <errno.h>
   7 #include <fcntl.h>
   8 #include <limits.h>
   9 #include <pthread.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <time.h>
  14 #include <unistd.h>
  15
  16 #include "common.h"
  17
  18 const size_t TIMESTAMP_LEN = 19;
  19
  20 typedef struct expectation {
  21   time_t a, b;
  22   const char *message;
  23 } ex_t;
  24
  25 const ex_t END = {((time_t)-1), ((time_t)-1), NULL};
  26 const ex_t CONSUMED = {((time_t)-2), ((time_t)-2), NULL};
  27 static int is_end(ex_t exp) {
  28   return exp.a == END.a && exp.b == END.b && exp.message == END.message;
  29 }
  30 static int is_consumed(ex_t exp) {
  31   return exp.a == CONSUMED.a && exp.b == CONSUMED.b &&
  32          exp.message == CONSUMED.message;
  33 }
  34 static ex_t expectation(time_t a, time_t b, const char *message) {
  35   ex_t exp;
  36   exp.a = a;
  37   exp.b = b;
  38   exp.message = message;
  39   return exp;
  40 }
  41
  42 static void remove_logfile() {
  43   if (remove(FILENAME) != 0) {
  44     if (errno != ENOENT) {
  45       die_err("Error removing log file");
  46     }
  47   }
  48 }
  49
  50 static ex_t write_to_tl_append(const char *content) {
  51   FILE *p = popen("./tl-append", "w");
  52   if (p == NULL)
  53     die_err("Couldn't run tl-append");
  54   time_t start = time(NULL);
  55   if (fputs(content, p) == EOF)
  56     die("Couldn't write to pipe");
  57   int status = pclose(p);
  58   time_t end = time(NULL);
  59   if (status < 0)
  60     die_err("Error closing pipe");
  61   if (status != 0)
  62     die("tl-append exited abnormally");
  63   return expectation(start, end, content);
  64 }
  65
  66 static char *timestamp_problem(const ex_t *ex, const char *line) {
  67   struct tm tm;
  68
  69   /* localtime_r to set tm's timezone */
  70   time_t now_time = time(NULL);
  71   if (localtime_r(&now_time, &tm) == NULL)
  72     return "Can't unpack current time?";
  73
  74   const char *strptime_result = strptime(line, "%Y %m %d %H %M %S", &tm);
  75   if (strptime_result == NULL || strptime_result != &line[TIMESTAMP_LEN])
  76     return "Wrong contents in log file: Couldn't parse timestamp";
  77   time_t t = mktime(&tm);
  78   int t_in_range = ex->a <= t && t <= ex->b;
  79   if (!t_in_range)
  80     return "Wrong contents in log file: Wrong time";
  81   return NULL;
  82 }
  83
  84 static char *line_problem(const ex_t *ex, const char *line) {
  85   size_t line_len = strlen(line);
  86   if (line_len < TIMESTAMP_LEN + 1)
  87     return "Wrong contents in log file: Line too short";
  88   char *trouble = timestamp_problem(ex, line);
  89   if (trouble)
  90     return trouble;
  91   if (line[TIMESTAMP_LEN] != ' ')
  92     return "Wrong contents in log file: Bad format";
  93   if (strncmp(ex->message, &line[TIMESTAMP_LEN + 1], strlen(ex->message) + 1) !=
  94       0)
  95     return "Wrong contents in log file";
  96   return NULL;
  97 }
  98
  99 static void verify_line(const ex_t *ex, const char *line) {
 100   char *trouble = line_problem(ex, line);
 101   if (trouble)
 102     die(trouble);
 103 }
 104
 105 static void verify_log_contents(const ex_t exps[]) {
 106   FILE *f = fopen(FILENAME, "r");
 107   if (f == NULL)
 108     die_err("Error opening log file");
 109   for (size_t i = 0; !is_end(exps[i]); i++) {
 110     size_t len = TIMESTAMP_LEN + 1 + strlen(exps[i].message);
 111     if (len > INT_MAX - 1)
 112       die("message too long");
 113     char *buf = (char *)malloc(len + 2);
 114     if (fgets(buf, len + 1, f) == NULL)
 115       die("Error reading log file");
 116     if (ferror(f))
 117       die("Error reading log file");
 118     verify_line(&exps[i], buf);
 119     free(buf);
 120   }
 121   if (fclose(f) != 0)
 122     die_err("Error closing log file");
 123 }
 124
 125 static void consume_expectation(ex_t exps[], const char *line) {
 126   for (size_t i = 0; !is_end(exps[i]); i++) {
 127     if (line_problem(&exps[i], line) == NULL) {
 128       exps[i] = CONSUMED;
 129       return;
 130     }
 131   }
 132   die("Wrong contents in log file: Line didn't match any expectation");
 133 }
 134
 135 static void verify_log_contents_unordered(ex_t exps[]) {
 136   FILE *f = fopen(FILENAME, "r");
 137   if (f == NULL)
 138     die_err("Error opening log file");
 139   for (;;) {
 140     const int MAX_LEN = 9999;
 141     char buf[MAX_LEN];
 142     if (fgets(buf, MAX_LEN, f) == NULL) {
 143       if (feof(f))
 144         break;
 145       die("Error reading log file");
 146     }
 147     if (ferror(f))
 148       die("Error reading log file");
 149     consume_expectation(exps, buf);
 150   }
 151   if (fclose(f) != 0)
 152     die_err("Error closing log file");
 153   for (size_t i = 0; !is_end(exps[i]); i++) {
 154     if (!is_consumed(exps[i]))
 155       die("Wrong contents in log file: Unconsumed expectation");
 156   }
 157 }
 158
 159 static void test_encode_time() {
 160   /* localtime_r to set tm's timezone */
 161   time_t now_time = time(NULL);
 162   struct tm tm;
 163   if (localtime_r(&now_time, &tm) == NULL)
 164     die_err("Can't unpack current time?");
 165
 166   const char *strptime_result = strptime("2011-12-13 14:15:16", "%F %T", &tm);
 167   if (strptime_result == NULL || *strptime_result != '\0')
 168     die("Couldn't parse time?");
 169   time_t tt = mktime(&tm);
 170   if (tt == (time_t)-1)
 171     die_err("Can't pack time?");
 172
 173   const char *encoded = encode_time(tt);
 174   /* Loose check to allow for daylight savings time changes between the current
 175    * time and the target time.  :( */
 176   assert(encoded[0] == '2');
 177   assert(encoded[1] == '0');
 178   assert(encoded[2] == '1');
 179   assert(encoded[3] == '1');
 180   assert(encoded[4] == ' ');
 181   assert(encoded[5] == '1');
 182   assert(encoded[6] == '2');
 183   assert(encoded[7] == ' ');
 184   assert(encoded[8] == '1');
 185   assert(encoded[9] == '3');
 186   assert(encoded[10] == ' ');
 187   assert(encoded[11] == '1');
 188   assert(isdigit(encoded[12]));
 189   assert(encoded[13] == ' ');
 190   assert(isdigit(encoded[14]));
 191   assert(isdigit(encoded[15]));
 192   assert(encoded[16] == ' ');
 193   assert(encoded[17] == '1');
 194   assert(encoded[18] == '6');
 195   assert(encoded[19] == '\0');
 196 }
 197
 198 static FILE *take_lock() {
 199   FILE *f = fopen(FILENAME, "a");
 200   if (f == NULL)
 201     die_err("Couldn't open file for locking");
 202   int fd = fileno(f);
 203   if (fd == -1)
 204     die_err("Couldn't get file descriptor for locking");
 205   if (fcntl(fd, F_SETLK,
 206             &(struct flock){.l_type = F_WRLCK,
 207                             .l_whence = SEEK_SET,
 208                             .l_start = 0,
 209                             .l_len = 0}) == -1)
 210     die_err("Couldn't take lock");
 211   return f;
 212 }
 213
 214 static void release_lock(FILE *f) {
 215   if (fclose(f) != 0)
 216     die_err("Error releasing lock");
 217 }
 218
 219 static void *release_lock_after_delay(void *f) {
 220   sleep(2);
 221   release_lock((FILE *)f);
 222   return NULL;
 223 }
 224
 225 static void *writer_thread(void *start_signal) {
 226   ex_t *ex = (ex_t *)malloc(sizeof(ex_t));
 227   if (ex == NULL)
 228     die_err("Couldn't allocate memory");
 229   char *message;
 230   if (asprintf(&message, "Hello from thread %lu\n", pthread_self()) == -1)
 231     die("Couldn't prepare message");
 232   pthread_rwlock_rdlock((pthread_rwlock_t *)start_signal);
 233   *ex = write_to_tl_append(message);
 234   return ex;
 235 }
 236
 237 static void write_and_read_line() {
 238   remove_logfile();
 239   ex_t e = write_to_tl_append("foo\n");
 240   verify_log_contents((ex_t[]){e, END});
 241 }
 242
 243 static void write_and_read_two_lines() {
 244   remove_logfile();
 245   ex_t e1 = write_to_tl_append("foo\n");
 246   ex_t e2 = write_to_tl_append("bar\n");
 247   verify_log_contents((ex_t[]){e1, e2, END});
 248 }
 249
 250 static void write_to_locked_log() {
 251   remove_logfile();
 252   ex_t e1 = write_to_tl_append("begin\n");
 253   FILE *lock = take_lock();
 254   pthread_t unlock_thread;
 255   int create_ret =
 256       pthread_create(&unlock_thread, NULL, &release_lock_after_delay, lock);
 257   if (create_ret != 0) {
 258     errno = create_ret;
 259     die_err("Couldn't start thread");
 260   }
 261   ex_t e2 = write_to_tl_append("delayed\n");
 262   int join_ret = pthread_join(unlock_thread, NULL);
 263   if (join_ret != 0) {
 264     errno = join_ret;
 265     die_err("Couldn't join thread");
 266   }
 267   verify_log_contents((ex_t[]){e1, e2, END});
 268 }
 269
 270 static void write_concurrently() {
 271   remove_logfile();
 272   const int PARALLELISM = 250;
 273   pthread_t threads[PARALLELISM];
 274   pthread_rwlock_t start_signal;
 275   pthread_rwlock_init(&start_signal, NULL);
 276   for (int i = 0; i < PARALLELISM; i++) {
 277     int create_ret =
 278         pthread_create(&threads[i], NULL, &writer_thread, &start_signal);
 279     if (create_ret != 0) {
 280       errno = create_ret;
 281       die_err("Couldn't start thread");
 282     }
 283   }
 284   pthread_rwlock_unlock(&start_signal);
 285   ex_t results[PARALLELISM + 1];
 286   for (int i = 0; i < PARALLELISM; i++) {
 287     ex_t *ex;
 288     int join_ret = pthread_join(threads[i], (void **)&ex);
 289     if (join_ret != 0) {
 290       errno = join_ret;
 291       die_err("Couldn't join thread");
 292     }
 293     results[i] = *ex;
 294     free(ex);
 295   }
 296   results[PARALLELISM] = END;
 297   verify_log_contents_unordered(results);
 298 }
 299
 300 int main() {
 301   test_encode_time();
 302   write_and_read_line();
 303   write_and_read_two_lines();
 304   write_to_locked_log();
 305   write_concurrently();
 306 }