linux-kernel/fake-serial/user-land/fsemul.c

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <stdlib.h>
   4 #include <assert.h>
   5 #include <readline/readline.h>
   6 #include <readline/history.h>
   7
   8 #define ULCMD_PROMPT "ulcmd>>> "
   9 #define FAKE_DEV_IBUFF_LEN 12
  10 #define END_CMD_CHAR '%'
  11
  12 struct fake_device {
  13         char *ibuf;
  14         char *lresult;
  15         int idx;
  16         size_t len;
  17 };
  18
  19 static char *responses[] = {
  20         "AT+A: hehehe\r",
  21         "AT+AB: muuu\r",
  22         "AT+FOO: bar\n",
  23         NULL
  24 };
  25
  26 static char *commands[] = {
  27         "AT+A%",
  28         "AT+AB%",
  29         "AT+FOO%",
  30         NULL
  31 };
  32
  33 static char *command_error = "ERROR: sua mula\r";
  34
  35 static void fake_device_rst_counters(struct fake_device *fake, int print_msg)
  36 {
  37         if (print_msg)
  38                 printf("-> Resetting counters\n");
  39         fake->idx = 0;
  40         fake->len = FAKE_DEV_IBUFF_LEN;
  41 }
  42
  43 static int fake_device_init(struct fake_device *fake, int print_msg)
  44 {
  45         fake_device_rst_counters(fake, print_msg);
  46         fake->lresult = NULL;
  47         fake->ibuf = malloc(fake->len);
  48         if (!fake->ibuf)
  49                 return -1;
  50         return 0;
  51 }
  52
  53 static void fake_device_del(struct fake_device *fake)
  54 {
  55         free(fake->ibuf);
  56 }
  57
  58 static void fake_device_ibuf_dump(struct fake_device *fake, FILE *stream)
  59 {
  60         char *p;
  61
  62         if (!fake->idx) {
  63                 fprintf(stream, "-> ibuf dump: Nothing to dump.\n");
  64                 return;
  65         }
  66
  67         fprintf(stream, "-> ibuf dump:\n");
  68
  69         for (p = fake->ibuf; (p - fake->ibuf) < fake->idx; p++)
  70                 fprintf(stream, "--> (%ld) 0x%x %c\n", p - fake->ibuf, *p, *p);
  71
  72         fprintf(stream, "--> idx: %d | len: %d\n", fake->idx, (int) fake->len);
  73 }
  74
  75 static int fake_device_handler(struct fake_device *fake)
  76 {
  77         char *p;
  78         int i, found = 0;
  79
  80         for (p = fake->ibuf; (p - fake->ibuf) < fake->idx; p++)
  81                 if (*p == END_CMD_CHAR) {
  82                         found = 1;
  83                         break;
  84                 }
  85
  86         if (!found) {
  87                 if (!fake->len)
  88                         fake_device_rst_counters(fake, 1);
  89                 return 0;
  90         }
  91
  92         /*
  93          * End of a command has been found
  94          */
  95
  96         for (i = 0; commands[i]; i++)
  97                 if (!strncmp(fake->ibuf, commands[i],
  98                                         (size_t) (p - fake->ibuf) + 1)) {
  99                         fake->lresult = responses[i];
 100                         goto out;
 101                 }
 102
 103         /* No valid command found */
 104         fake->lresult = command_error;
 105 out:
 106         fake_device_rst_counters(fake, 1);
 107         return 1;
 108 }
 109
 110 int main(void)
 111 {
 112         int ret;
 113         char *line;
 114         size_t line_len;
 115         struct fake_device fake;
 116
 117         fake_device_init(&fake, 0);
 118
 119         for (;;) {
 120                 line = readline(ULCMD_PROMPT);
 121                 if (!line) {
 122                         printf("\nExiting...\n");
 123                         return 0;
 124                 }
 125                 printf("-> Line read is: %s\n", line);
 126
 127                 line_len = strlen(line);
 128                 strncpy(fake.ibuf + fake.idx, line, fake.len);
 129                 if (line_len > fake.len) {
 130                         fake.idx += fake.len;
 131                         fake.len = 0;
 132                 } else {
 133                         fake.idx += line_len;
 134                         fake.len -= line_len;
 135                 }
 136
 137                 fake_device_ibuf_dump(&fake, stdout);
 138                 ret = fake_device_handler(&fake);
 139                 if (ret) {
 140                         assert(fake.lresult != NULL);
 141                         printf("-> Command response: %s\n", fake.lresult);
 142                         fake.lresult = NULL;
 143                 }
 144         }
 145
 146         fake_device_del(&fake);
 147         return 0;
 148 }