| 1 | #define _GNU_SOURCE |
| 2 | |
| 3 | #include <sys/types.h> |
| 4 | #include <sys/shm.h> |
| 5 | #include <fcntl.h> |
| 6 | #include <unistd.h> |
| 7 | |
| 8 | #include <stdlib.h> |
| 9 | #include <stdio.h> |
| 10 | #include <string.h> |
| 11 | |
| 12 | #include "localerr.h" |
| 13 | #include "ustcomm.h" |
| 14 | |
| 15 | struct list_head buffers = LIST_HEAD_INIT(buffers); |
| 16 | |
| 17 | struct buffer_info { |
| 18 | char *name; |
| 19 | pid_t pid; |
| 20 | |
| 21 | int shmid; |
| 22 | void *mem; |
| 23 | int memlen; |
| 24 | |
| 25 | int n_subbufs; |
| 26 | int subbuf_size; |
| 27 | |
| 28 | int file_fd; /* output file */ |
| 29 | |
| 30 | struct list_head list; |
| 31 | |
| 32 | long consumed_old; |
| 33 | }; |
| 34 | |
| 35 | int add_buffer(pid_t pid, char *bufname) |
| 36 | { |
| 37 | struct buffer_info *buf; |
| 38 | char *send_msg; |
| 39 | char *received_msg; |
| 40 | int result; |
| 41 | char *tmp; |
| 42 | int fd; |
| 43 | |
| 44 | buf = (struct buffer_info *) malloc(sizeof(struct buffer_info)); |
| 45 | if(buf == NULL) { |
| 46 | ERR("add_buffer: insufficient memory"); |
| 47 | return -1; |
| 48 | } |
| 49 | |
| 50 | buf->name = bufname; |
| 51 | buf->pid = pid; |
| 52 | |
| 53 | /* get shmid */ |
| 54 | asprintf(&send_msg, "get_shmid %s", buf->name); |
| 55 | send_message(pid, send_msg, &received_msg); |
| 56 | free(send_msg); |
| 57 | DBG("got buffer name %s", buf->name); |
| 58 | |
| 59 | result = sscanf(received_msg, "%d", &buf->shmid); |
| 60 | if(result != 1) { |
| 61 | ERR("unable to parse response to get_shmid"); |
| 62 | return -1; |
| 63 | } |
| 64 | free(received_msg); |
| 65 | DBG("got shmid %d", buf->shmid); |
| 66 | |
| 67 | /* get n_subbufs */ |
| 68 | asprintf(&send_msg, "get_n_subbufs %s", buf->name); |
| 69 | send_message(pid, send_msg, &received_msg); |
| 70 | free(send_msg); |
| 71 | |
| 72 | result = sscanf(received_msg, "%d", &buf->n_subbufs); |
| 73 | if(result != 1) { |
| 74 | ERR("unable to parse response to get_n_subbufs"); |
| 75 | return -1; |
| 76 | } |
| 77 | free(received_msg); |
| 78 | DBG("got n_subbufs %d", buf->n_subbufs); |
| 79 | |
| 80 | /* get subbuf size */ |
| 81 | asprintf(&send_msg, "get_subbuf_size %s", buf->name); |
| 82 | send_message(pid, send_msg, &received_msg); |
| 83 | free(send_msg); |
| 84 | |
| 85 | result = sscanf(received_msg, "%d", &buf->subbuf_size); |
| 86 | if(result != 1) { |
| 87 | ERR("unable to parse response to get_subbuf_size"); |
| 88 | return -1; |
| 89 | } |
| 90 | free(received_msg); |
| 91 | DBG("got subbuf_size %d", buf->subbuf_size); |
| 92 | |
| 93 | /* attach memory */ |
| 94 | buf->mem = shmat(buf->shmid, NULL, 0); |
| 95 | if(buf->mem == (void *) 0) { |
| 96 | perror("shmat"); |
| 97 | return -1; |
| 98 | } |
| 99 | DBG("successfully attached memory"); |
| 100 | |
| 101 | /* open file for output */ |
| 102 | asprintf(&tmp, "/tmp/trace/%s_0", buf->name); |
| 103 | result = fd = open(tmp, O_WRONLY | O_CREAT | O_TRUNC, 00600); |
| 104 | if(result == -1) { |
| 105 | PERROR("open"); |
| 106 | return -1; |
| 107 | } |
| 108 | buf->file_fd = fd; |
| 109 | free(tmp); |
| 110 | |
| 111 | list_add(&buf->list, &buffers); |
| 112 | |
| 113 | return 0; |
| 114 | } |
| 115 | |
| 116 | int get_subbuffer(struct buffer_info *buf) |
| 117 | { |
| 118 | char *send_msg; |
| 119 | char *received_msg; |
| 120 | char *rep_code; |
| 121 | int retval; |
| 122 | int result; |
| 123 | |
| 124 | asprintf(&send_msg, "get_subbuffer %s", buf->name); |
| 125 | result = send_message(buf->pid, send_msg, &received_msg); |
| 126 | if(result < 0) { |
| 127 | ERR("get_subbuffer: send_message failed"); |
| 128 | return -1; |
| 129 | } |
| 130 | free(send_msg); |
| 131 | |
| 132 | result = sscanf(received_msg, "%as %ld", &rep_code, &buf->consumed_old); |
| 133 | if(result != 2) { |
| 134 | ERR("unable to parse response to get_subbuffer"); |
| 135 | return -1; |
| 136 | } |
| 137 | free(received_msg); |
| 138 | |
| 139 | if(!strcmp(rep_code, "OK")) { |
| 140 | DBG("got subbuffer %s", buf->name); |
| 141 | retval = 1; |
| 142 | } |
| 143 | else { |
| 144 | DBG("did not get subbuffer %s", buf->name); |
| 145 | retval = 0; |
| 146 | } |
| 147 | |
| 148 | free(rep_code); |
| 149 | return retval; |
| 150 | } |
| 151 | |
| 152 | int put_subbuffer(struct buffer_info *buf) |
| 153 | { |
| 154 | char *send_msg; |
| 155 | char *received_msg; |
| 156 | char *rep_code; |
| 157 | int retval; |
| 158 | int result; |
| 159 | |
| 160 | asprintf(&send_msg, "put_subbuffer %s %ld", buf->name, buf->consumed_old); |
| 161 | result = send_message(buf->pid, send_msg, &received_msg); |
| 162 | if(result < 0) { |
| 163 | ERR("put_subbuffer: send_message failed"); |
| 164 | return -1; |
| 165 | } |
| 166 | free(send_msg); |
| 167 | |
| 168 | result = sscanf(received_msg, "%as", &rep_code); |
| 169 | if(result != 1) { |
| 170 | ERR("unable to parse response to put_subbuffer"); |
| 171 | return -1; |
| 172 | } |
| 173 | free(received_msg); |
| 174 | |
| 175 | if(!strcmp(rep_code, "OK")) { |
| 176 | DBG("subbuffer put %s", buf->name); |
| 177 | retval = 1; |
| 178 | } |
| 179 | else { |
| 180 | ERR("invalid response to put_subbuffer"); |
| 181 | } |
| 182 | |
| 183 | free(rep_code); |
| 184 | return retval; |
| 185 | } |
| 186 | |
| 187 | ssize_t patient_write(int fd, const void *buf, size_t count) |
| 188 | { |
| 189 | const char *bufc = (const char *) buf; |
| 190 | int result; |
| 191 | |
| 192 | for(;;) { |
| 193 | result = write(fd, bufc, count); |
| 194 | if(result <= 0) { |
| 195 | return result; |
| 196 | } |
| 197 | count -= result; |
| 198 | bufc += result; |
| 199 | |
| 200 | if(count == 0) { |
| 201 | break; |
| 202 | } |
| 203 | } |
| 204 | |
| 205 | return bufc-(const char *)buf; |
| 206 | } |
| 207 | |
| 208 | int main(int argc, char **argv) |
| 209 | { |
| 210 | struct ustcomm_ustd ustd; |
| 211 | int result; |
| 212 | |
| 213 | result = ustcomm_init_ustd(&ustd); |
| 214 | if(result == -1) { |
| 215 | ERR("failed to initialize socket"); |
| 216 | return 1; |
| 217 | } |
| 218 | |
| 219 | /* app loop */ |
| 220 | for(;;) { |
| 221 | char *recvbuf; |
| 222 | struct buffer_info *buf; |
| 223 | |
| 224 | /* 1. check for requests on our public socket */ |
| 225 | result = ustcomm_ustd_recv_message(&ustd, &recvbuf, NULL, 100); |
| 226 | if(result == -1) { |
| 227 | ERR("error in ustcomm_ustd_recv_message"); |
| 228 | continue; |
| 229 | } |
| 230 | if(result > 0) { |
| 231 | if(!strncmp(recvbuf, "collect", 7)) { |
| 232 | pid_t pid; |
| 233 | char *bufname; |
| 234 | int result; |
| 235 | |
| 236 | result = sscanf(recvbuf, "%*s %d %50as", &pid, &bufname); |
| 237 | if(result != 2) { |
| 238 | fprintf(stderr, "parsing error: %s\n", recvbuf); |
| 239 | } |
| 240 | |
| 241 | result = add_buffer(pid, bufname); |
| 242 | if(result < 0) { |
| 243 | ERR("error in add_buffer"); |
| 244 | continue; |
| 245 | } |
| 246 | } |
| 247 | |
| 248 | free(recvbuf); |
| 249 | } |
| 250 | |
| 251 | /* 2. try to consume data from tracing apps */ |
| 252 | list_for_each_entry(buf, &buffers, list) { |
| 253 | result = get_subbuffer(buf); |
| 254 | if(result == -1) { |
| 255 | ERR("error getting subbuffer"); |
| 256 | continue; |
| 257 | } |
| 258 | if(result == 0) |
| 259 | continue; |
| 260 | |
| 261 | /* write data to file */ |
| 262 | //result = write(buf->file_fd, buf->, ); |
| 263 | result = patient_write(buf->file_fd, buf->mem + (buf->consumed_old & (buf->n_subbufs * buf->subbuf_size-1)), buf->subbuf_size); |
| 264 | if(result == -1) { |
| 265 | PERROR("write"); |
| 266 | /* FIXME: maybe drop this trace */ |
| 267 | } |
| 268 | |
| 269 | result = put_subbuffer(buf); |
| 270 | if(result == -1) { |
| 271 | ERR("error putting subbuffer"); |
| 272 | } |
| 273 | } |
| 274 | } |
| 275 | |
| 276 | return 0; |
| 277 | } |