root / mainbox / util.c @ ea46eeca
History | View | Annotate | Download (1.99 KB)
| 1 | 15928a3d | Tom Mullins | #include "util.h" |
|---|---|---|---|
| 2 | 5e03b78d | Tom Mullins | #include "log.h" |
| 3 | 15928a3d | Tom Mullins | #include <stdlib.h> |
| 4 | #include <stdio.h> |
||
| 5 | ea46eeca | Tom Mullins | #include <string.h> |
| 6 | cc7646f9 | Tom Mullins | #include <errno.h> |
| 7 | 15928a3d | Tom Mullins | #include <unistd.h> |
| 8 | #include <sys/types.h> |
||
| 9 | #include <sys/stat.h> |
||
| 10 | #include <fcntl.h> |
||
| 11 | |||
| 12 | ea46eeca | Tom Mullins | #define BUF_SIZE 1024 |
| 13 | |||
| 14 | cc7646f9 | Tom Mullins | /*
|
| 15 | * read_file
|
||
| 16 | *
|
||
| 17 | ea46eeca | Tom Mullins | * Reads the first line of a file. Returns NULL on error, or a pointer to a
|
| 18 | * malloc'd string which should later be freed.
|
||
| 19 | cc7646f9 | Tom Mullins | */
|
| 20 | 15928a3d | Tom Mullins | char *read_file(const char *filename) { |
| 21 | ea46eeca | Tom Mullins | char buf[BUF_SIZE];
|
| 22 | int len;
|
||
| 23 | FILE *file; |
||
| 24 | |||
| 25 | file = fopen(filename, "r");
|
||
| 26 | if (file == NULL) { |
||
| 27 | 13fd9e7e | Tom Mullins | log_perror(filename); |
| 28 | 15928a3d | Tom Mullins | return NULL; |
| 29 | } |
||
| 30 | |||
| 31 | ea46eeca | Tom Mullins | fgets(buf, BUF_SIZE, file); |
| 32 | |||
| 33 | if (ferror(file)) {
|
||
| 34 | log_perror(filename); |
||
| 35 | fclose(file); |
||
| 36 | 15928a3d | Tom Mullins | return NULL; |
| 37 | } |
||
| 38 | |||
| 39 | ea46eeca | Tom Mullins | len = strlen(buf); |
| 40 | if (len > 0 && buf[len-1] == '\n') |
||
| 41 | buf[len-1] = '\0'; |
||
| 42 | |||
| 43 | fclose(file); |
||
| 44 | return strdup(buf);
|
||
| 45 | 15928a3d | Tom Mullins | } |
| 46 | cc7646f9 | Tom Mullins | |
| 47 | /*
|
||
| 48 | * create_pid_file
|
||
| 49 | *
|
||
| 50 | 13fd9e7e | Tom Mullins | * Creates PIDFILE containing the PID of the current process. Returns 0 if
|
| 51 | * successful, or nonzero if there is an error or it already exists.
|
||
| 52 | cc7646f9 | Tom Mullins | */
|
| 53 | int create_pid_file() {
|
||
| 54 | int fd;
|
||
| 55 | FILE *file; |
||
| 56 | |||
| 57 | 13fd9e7e | Tom Mullins | fd = open(PIDFILE, O_CREAT | O_EXCL | O_WRONLY, 0644);
|
| 58 | cc7646f9 | Tom Mullins | if (fd < 0) { |
| 59 | if (errno == EEXIST)
|
||
| 60 | fprintf(stderr, "ERROR: tooltron is already running, or the pidfile "
|
||
| 61 | ddd50354 | Tom Mullins | PIDFILE " is stale");
|
| 62 | cc7646f9 | Tom Mullins | else
|
| 63 | 13fd9e7e | Tom Mullins | log_perror(PIDFILE); |
| 64 | cc7646f9 | Tom Mullins | return 1; |
| 65 | } |
||
| 66 | |||
| 67 | file = fdopen(fd, "w");
|
||
| 68 | if (!file) {
|
||
| 69 | log_perror("fdopen");
|
||
| 70 | return 1; |
||
| 71 | } |
||
| 72 | |||
| 73 | fprintf(file, "%d", getpid());
|
||
| 74 | |||
| 75 | fclose(file); |
||
| 76 | return 0; |
||
| 77 | } |
||
| 78 | |||
| 79 | /*
|
||
| 80 | * remove_pid_file
|
||
| 81 | *
|
||
| 82 | 13fd9e7e | Tom Mullins | * Removes PIDFILE.
|
| 83 | cc7646f9 | Tom Mullins | */
|
| 84 | void remove_pid_file() {
|
||
| 85 | 13fd9e7e | Tom Mullins | if (unlink(PIDFILE))
|
| 86 | log_perror(PIDFILE); |
||
| 87 | cc7646f9 | Tom Mullins | } |
| 88 | |||
| 89 | /*
|
||
| 90 | * read_pid_file
|
||
| 91 | *
|
||
| 92 | 13fd9e7e | Tom Mullins | * Returns the integer found in PIDFILE, or 0 if there was an
|
| 93 | cc7646f9 | Tom Mullins | * error.
|
| 94 | */
|
||
| 95 | pid_t read_pid_file() {
|
||
| 96 | FILE *file; |
||
| 97 | int pid;
|
||
| 98 | |||
| 99 | 13fd9e7e | Tom Mullins | file = fopen(PIDFILE, "r");
|
| 100 | cc7646f9 | Tom Mullins | if (!file) {
|
| 101 | if (errno == ENOENT)
|
||
| 102 | fprintf(stderr, "ERROR: tooltron does not appear to be running\n");
|
||
| 103 | else
|
||
| 104 | 13fd9e7e | Tom Mullins | perror(PIDFILE); |
| 105 | cc7646f9 | Tom Mullins | return 0; |
| 106 | } |
||
| 107 | |||
| 108 | if (fscanf(file, "%d", &pid) != 1) { |
||
| 109 | perror("fscanf");
|
||
| 110 | fclose(file); |
||
| 111 | return 0; |
||
| 112 | } |
||
| 113 | |||
| 114 | fclose(file); |
||
| 115 | return pid;
|
||
| 116 | } |