wmbiff/wmbiff/ShellClient.c

   1 /* Author: Benoît Rouits ( brouits@free.fr ) thanks to Neil Spring.
   2    from LicqClient by Yong-iL Joh ( tolkien@mizi.com )
   3    and Jorge García ( Jorge.Garcia@uv.es )
   4  *
   5  * generic Shell command support
   6  *
   7  * Last Updated : Tue Mar  5 15:23:35 CET 2002
   8  *
   9  */
  10
  11 #ifdef HAVE_CONFIG_H
  12 #include <config.h>
  13 #endif
  14
  15 #include "Client.h"
  16 #include <errno.h>
  17 #include <string.h>
  18 #include <stdio.h>
  19 #include <ctype.h>
  20 #include <signal.h>
  21 #include <assert.h>
  22 #include <strings.h>
  23 #include "charutil.h"
  24 #include "MessageList.h"
  25 #ifdef USE_DMALLOC
  26 #include <dmalloc.h>
  27 #endif
  28
  29 #define SH_DM(pc, lvl, args...) DM(pc, lvl, "shell: " args)
  30
  31 /* kind_popen bumps off the sigchld handler - we care whether
  32    a checking program fails. */
  33
  34 #ifdef __LCLINT__
  35 void (*old_signal_handler) (int);
  36 #else
  37 RETSIGTYPE(*old_signal_handler) (int);
  38 #endif
  39
  40 /*@null@*/
  41 FILE *kind_popen(const char *command, const char *type)
  42 {
  43         FILE *ret;
  44         assert(strcmp(type, "r") == 0);
  45         assert(old_signal_handler == NULL);
  46         old_signal_handler = signal(SIGCHLD, SIG_DFL);
  47         ret = popen(command, type);
  48         if (ret == NULL) {
  49                 DMA(DEBUG_ERROR, "popen: error while reading '%s': %s\n",
  50                         command, strerror(errno));
  51                 (void) signal(SIGCHLD, old_signal_handler);
  52                 old_signal_handler = NULL;
  53         }
  54         return (ret);
  55 }
  56
  57 /* kind_pclose checks the return value from pclose and prints
  58    some nice error messages about it.  ordinarily, this would be
  59    a good idea, but wmbiff has a sigchld handler that reaps
  60    children immediately (needed when spawning other child processes),
  61    so no error checking can be done here until that's disabled */
  62
  63 /* returns as a mailcheck function does: -1 on fail, 0 on success */
  64 static int kind_pclose( /*@only@ */ FILE * F,
  65                                            const char *command,
  66                                            /*@null@ */ Pop3 pc)
  67 {
  68         int exit_status = pclose(F);
  69
  70         if (old_signal_handler != NULL) {
  71                 (void) signal(SIGCHLD, old_signal_handler);
  72                 old_signal_handler = NULL;
  73         }
  74
  75         if (exit_status != 0) {
  76                 if (exit_status == -1) {
  77                         /* wmbiff has a sigchld handler already, so wait is likely
  78                            to fail */
  79                         SH_DM(pc, DEBUG_ERROR, "pclose '%s' failed: %s\n",
  80                                   command, strerror(errno));
  81                 } else {
  82                         SH_DM(pc, DEBUG_ERROR,
  83                                   "'%s' exited with non-zero status %d\n", command,
  84                                   exit_status);
  85                 }
  86         }
  87         return (exit_status);
  88 }
  89
  90 int grabCommandOutput(Pop3 pc, const char *command,     /*@out@ */
  91                                           char **output, /*@out@ *//*@null@ */ char **details)
  92 {
  93         FILE *F;
  94         char linebuf[512];
  95         SH_DM(pc, DEBUG_INFO, "Executing '%s'\n", command);
  96         *output = NULL;
  97         if ((F = kind_popen(command, "r")) == NULL) {
  98                 return -1;
  99         }
 100         if (fgets(linebuf, 512, F) == NULL) {
 101                 SH_DM(pc, DEBUG_ERROR,
 102                           "fgets: unable to read the output of '%s': %s\n", command,
 103                           strerror(errno));
 104         } else {
 105                 chomp(linebuf);                 /* remove trailing newline */
 106                 *output = strdup_ordie(linebuf);
 107         }
 108         if (details) {
 109                 static char allbuf[4096];
 110                 allbuf[0] = '\0';
 111                 if (fread(allbuf, 1, 4095, F) == 0 && !feof(F)) {
 112                         SH_DM(pc, DEBUG_ERROR,
 113                                   "fread: unable to read the detailed output of '%s': %s\n",
 114                                   command, strerror(errno));
 115                 }
 116                 allbuf[4095] = '\0';
 117                 *details = strdup_ordie(allbuf);
 118         }
 119         return (kind_pclose(F, command, pc));
 120 }
 121
 122 /* returns null on failure */
 123 /*@null@*/
 124 char *backtickExpand(Pop3 pc, const char *path)
 125 {
 126         char bigbuffer[1024];
 127         const char *tickstart;
 128         const char *tickend;
 129         bigbuffer[0] = '\0';
 130         while ((tickstart = strchr(path, '`')) != NULL) {
 131                 char *command;
 132                 char *commandoutput;
 133                 tickend = strchr(tickstart + 1, '`');
 134                 if (tickend == NULL) {
 135                         SH_DM(pc, DEBUG_ERROR, "unbalanced \' in %s\n", path);
 136                         return NULL;
 137                 }
 138                 strncat(bigbuffer, path, tickstart - path);
 139                 command = strdup_ordie(tickstart + 1);
 140                 command[tickend - tickstart - 1] = '\0';
 141                 (void) grabCommandOutput(pc, command, &commandoutput, NULL);
 142                 free(command);
 143                 if (commandoutput != NULL) {
 144                         strcat(bigbuffer, commandoutput);
 145                         free(commandoutput);
 146                 }
 147                 path = tickend + 1;
 148         }
 149         /* grab the rest */
 150         strcat(bigbuffer, path);
 151         SH_DM(pc, DEBUG_INFO, "expanded to %s\n", bigbuffer);
 152         return (strdup_ordie(bigbuffer));
 153 }
 154
 155 int shellCmdCheck(Pop3 pc)
 156 {
 157         int count_status = 0;
 158         char *commandOutput;
 159
 160         if (pc == NULL)
 161                 return -1;
 162         SH_DM(pc, DEBUG_INFO, ">Mailbox: '%s'\n", pc->path);
 163
 164         /* fetch the first line of input */
 165         pc->TextStatus[0] = '\0';
 166         if (pc->u.shell.detail != NULL) {
 167                 free(pc->u.shell.detail);
 168                 pc->u.shell.detail = NULL;
 169         }
 170         (void) grabCommandOutput(pc, pc->path, &commandOutput,
 171                                                          &pc->u.shell.detail);
 172         if (commandOutput == NULL) {
 173                 return -1;
 174         }
 175         SH_DM(pc, DEBUG_INFO, "'%s' returned '%s'\n", pc->path, commandOutput);
 176
 177         /* see if it's numeric; the numeric check is somewhat
 178            useful, as wmbiff renders 4-digit numbers, but not
 179            4-character strings. */
 180         if (sscanf(commandOutput, "%d", &(count_status)) == 1) {
 181                 if (strstr(commandOutput, "new")) {
 182                         pc->UnreadMsgs = count_status;
 183                         pc->TotalMsgs = 0;
 184                 } else if (strstr(commandOutput, "old")) {
 185                         pc->UnreadMsgs = 0;
 186                         pc->TotalMsgs = count_status;
 187                 } else {
 188                         /* this default should be configurable. */
 189                         pc->UnreadMsgs = 0;
 190                         pc->TotalMsgs = count_status;
 191                 }
 192         } else if (strcasestr(commandOutput, "unable")) {
 193                 return -1;
 194         } else if (sscanf(commandOutput, "%9s\n", pc->TextStatus) == 1) {
 195                 /* validate the string input */
 196                 int i;
 197                 for (i = 0; pc->TextStatus[i] != '\0' && isalnum(pc->TextStatus[i])
 198                          && i < 10; i++);
 199                 if (pc->TextStatus[i] != '\0') {
 200                         SH_DM(pc, DEBUG_ERROR,
 201                                   "wmbiff only supports alphanumeric (isalnum) strings:\n"
 202                                   " '%s' is not ok\n", pc->TextStatus);
 203                         /* null terminate it at the first bad char: */
 204                         pc->TextStatus[i] = '\0';
 205                 }
 206                 /* see if we should print as new or not */
 207                 pc->UnreadMsgs = (strstr(commandOutput, "new")) ? 1 : 0;
 208                 pc->TotalMsgs = -1;             /* we might alternat numeric /string */
 209         } else {
 210                 SH_DM(pc, DEBUG_ERROR,
 211                           "'%s' returned something other than an integer message count"
 212                           " or short string.\n", pc->path);
 213                 free(commandOutput);
 214                 return -1;
 215         }
 216
 217         SH_DM(pc, DEBUG_INFO, "from: %s status: %s %d %d\n",
 218                   pc->path, pc->TextStatus, pc->TotalMsgs, pc->UnreadMsgs);
 219         free(commandOutput);
 220         return (0);
 221 }
 222
 223 struct msglst *shell_getHeaders( /*@notnull@ */ Pop3 pc)
 224 {
 225         struct msglst *message_list = NULL;
 226
 227         char *ln = pc->u.shell.detail;
 228         int i, j;
 229         if (ln == NULL)
 230                 return NULL;
 231
 232         for (j = 0; ln[j] != '\0';) {
 233                 struct msglst *m = malloc(sizeof(struct msglst));
 234                 m->next = message_list;
 235                 m->subj[0] = '\0';
 236                 m->from[0] = '\0';
 237
 238                 for (i = 0; i < SUBJ_LEN - 1 && ln[j + i] != '\n'; i++) {
 239                         m->subj[i] = ln[j + i];
 240                 }
 241                 m->subj[i] = '\0';
 242                 j += i + 1;
 243
 244                 message_list = m;
 245         }
 246         return message_list;
 247 }
 248
 249 void
 250 shell_releaseHeaders(Pop3 pc __attribute__ ((unused)), struct msglst *h)
 251 {
 252         for (; h != NULL;) {
 253                 struct msglst *n = h->next;
 254                 free(h);
 255                 h = n;
 256         }
 257 }
 258
 259 int shellCreate( /*@notnull@ */ Pop3 pc, const char *str)
 260 {
 261         /* SHELL format: shell:::/path/to/script */
 262         const char *reserved1, *reserved2, *commandline;
 263
 264         pc->TotalMsgs = 0;
 265         pc->UnreadMsgs = 0;
 266         pc->OldMsgs = -1;
 267         pc->OldUnreadMsgs = -1;
 268         pc->checkMail = shellCmdCheck;
 269         pc->getHeaders = shell_getHeaders;
 270         reserved1 = str + 6;            /* shell:>:: */
 271
 272         assert(strncasecmp("shell:", str, 6) == 0);
 273
 274         reserved2 = index(reserved1, ':');
 275         if (reserved2 == NULL) {
 276                 SH_DM(pc, DEBUG_ERROR, "unable to parse '%s', expecting ':'", str);
 277                 return 0;
 278         }
 279         reserved2++;                            /* shell::>: */
 280
 281         commandline = index(reserved2, ':');
 282         if (commandline == NULL) {
 283                 SH_DM(pc, DEBUG_ERROR,
 284                           "unable to parse '%s', expecting another ':'", str);
 285                 return 0;
 286         }
 287         commandline++;                          /* shell:::> */
 288
 289         /* strcpy is not specified to handle overlapping regions */
 290         SH_DM(pc, DEBUG_INFO, "path= '%s'\n", commandline);
 291         {
 292                 char *tmp = strdup(commandline);
 293                 if (strlen(tmp) + 1 > BUF_BIG) {
 294                         SH_DM(pc, DEBUG_ERROR, "commandline '%s' is too long.\n",
 295                                   commandline);
 296                         memset(pc->path, 0, BUF_BIG);
 297                 } else {
 298                         strcpy(pc->path, tmp);
 299                 }
 300                 free(tmp);
 301         }
 302         return 0;
 303 }
 304
 305 /* vim:set ts=4: */
 306 /*
 307  * Local Variables:
 308  * tab-width: 4
 309  * c-indent-level: 4
 310  * c-basic-offset: 4
 311  * End:
 312  */