Some cleanup before 1.0 release (#9)

* Add buffer length flag, improve crash report

* Remove printf

src/help_str.txt

@@ -29,6 +29,11 @@ Options:
     For the receiver this will be the (non pre-existing) file into which
     to copy the contents received from the sender
 
+--length-buff <size in kb>, -l <size in kb>
+    Use this option with a shared memory sender to specify the size (in kB)
+    of each chunk that will be copied. The total shared memory usage will be
+    slightly more than twice the size of the chunk
+
 Role, method and filename can also be passed as naked arguments in this
 order
 

src/main.c

@@ -29,7 +29,7 @@ int main(int argc, char **argv)
     {"file", required_argument, NULL, 'f'},
     {"role", required_argument, NULL, 'r'},
     {"method", required_argument, NULL, 'm'},
-    {"max_pages", required_argument, NULL, 'l'},
+    {"length-buff", required_argument, NULL, 'l'},
     {"help", no_argument, NULL, 'h'},
     {0, 0, NULL, 0}
   };
@@ -84,7 +84,7 @@ int main(int argc, char **argv)
       break;
     case 'l':
     if (flag_max_pages){
-      err_and_leave("Too many definitions of max_pages", 1);
+      err_and_leave("Too many definitions of buffer length", 1);
       } else {
         flag_max_pages = 1;
         }
@@ -155,6 +155,11 @@ int main(int argc, char **argv)
     all_flags &= 0;
   }
 
+  if ((settings.method==SHARED) && (settings.role == SENDER) && !flag_max_pages){
+    printf("Setting default buffer size to 2 kb, use the -l flag to set manually\n");
+    settings.max_pages = 2;
+  }
+
   if (!all_flags){
     printf("Use --help to get more informations on how to use the program\n");
     return 3;

src/pipe/pipe.c

@@ -10,7 +10,7 @@
 #define BUFFSZ 256
 
 int use_pipe(setting_t settings){
-    printf("usp %s\n", settings.password);
+    //printf("usp %s\n", settings.password);
     switch (settings.role) {
         case SENDER:
             return pipe_sender(settings);
@@ -25,7 +25,7 @@ int use_pipe(setting_t settings){
 }
 
 char* fifo_name(char* passwd){
-    printf("ffn %s\n", passwd);
+    //printf("ffn %s\n", passwd);
     char* myfifo = "/tmp/myfifo_";
     // We have passwd
     // We have myfifo
@@ -39,9 +39,9 @@ char* fifo_name(char* passwd){
 }
 
 char* create_fifo(char* passwd){
-    printf("ffn %s\n", passwd);
+    //printf("ffn %s\n", passwd);
     char* new_string = fifo_name(passwd);
-    printf("%s\n", new_string);
+    //printf("%s\n", new_string);
     int ret = mkfifo(new_string, 0666);
     if (ret == 0){
     } else if (ret == -1) {
@@ -50,8 +50,7 @@ char* create_fifo(char* passwd){
         case EEXIST:
             break;
         default:
-
-        printf("%d\n", errno);
+            printf("%d\n", errno);
             err_and_leave("Failed to create pipe", 4);
             break;
         }

src/shm/shm.c

@@ -14,12 +14,12 @@ mmap_creat_ret_t access_or_create_coord(char* passwd){
     strcat(path, passwd);
 
     int fdm = shm_open(path, O_CREAT | O_EXCL | O_RDWR, 0660);
-    printf("opn_sync %d %d\n", fdm, errno);
+    //printf("opn_sync %d %d\n", fdm, errno);
     if (fdm == -1){
         if (errno == EEXIST){
             fdm = shm_open(path, O_RDWR, 0);
             coord_struct* str = (coord_struct*) mmap(NULL, sizeof(coord_struct), PROT_READ | PROT_WRITE, MAP_SHARED, fdm, 0);
-            printf("mmp sync %p %d\n", str, errno);
+            //printf("mmp sync %p %d\n", str, errno);
             return (mmap_creat_ret_t){.mem_region=str, .fd_shared=fdm, .path=path};
         } else {
             err_and_leave("Error when accessing shared memory", 5);
@@ -49,17 +49,18 @@ mmap_creat_ret_t init_copy_area(char* passwd, size_t width, size_t* mmap_size){
     char *path = path_copy(passwd);
     { // Create file for shared_memory
         fdm = shm_open(path, O_CREAT | O_EXCL | O_RDWR, 0660);
-        printf("opn_cp_shm %d %d\n", fdm, errno);
+        //printf("opn_cp_shm %d %d\n", fdm, errno);
         if (fdm == -1){
             err_and_leave("Error when creating file-specific sharedmemory", 5);
         }
     }
     size_t m_sz = sizeof(copy_struct) + (2*width);
+    //printf("Size of copy area: %ld + 2*%ld = %ld\n", sizeof(copy_struct), width, m_sz);
     *mmap_size = m_sz;
     ftruncate(fdm, m_sz);
     copy_struct* copy_mem = (copy_struct*) mmap(NULL, m_sz, PROT_READ | PROT_WRITE, MAP_SHARED, fdm, 0);
 
-    printf("cmm %p %d\n", copy_mem, errno);
+    //printf("cmm %p %d\n", copy_mem, errno);
     init_cond_pack(&(copy_mem->signal_wrtr));
 
 
@@ -103,10 +104,18 @@ int shared_sender(setting_t settings, int lockfd, mmap_creat_ret_t mmap_info){
     pthread_mutex_lock(&(coord->lock)); // Prevent any other thread from joining
     pthread_mutex_lock(&(coord->writer_ready.lock));
     if (coord->writer_ready.v != 0){
+        char *cpath = path_copy(settings.password);
+        printf("A writer seems to be already using this memory area, try to use\n"
+               "a different password. If the previous program crashed manually\n"
+               "delete the files:\n"
+               "- /dev/shm%s\n"
+               "- /dev/shm%s\n", mmap_info.path, cpath);
         return 1;
     }
 
-    mmap_creat_ret_t ret_copy_init = init_copy_area(settings.password, DEFAULT_WIDTH, &(coord->mmap_size));
+    size_t width = settings.max_pages * 1024;
+
+    mmap_creat_ret_t ret_copy_init = init_copy_area(settings.password, width, &(coord->mmap_size));
     copy_struct* copy = (copy_struct*) ret_copy_init.mem_region;
 
     // Lock the first active area, now it's ready to accept readers
@@ -217,7 +226,7 @@ int shared_receiver(setting_t settings, int lockfd, mmap_creat_ret_t mmap_info){
     int fdm;
     { // Create file for shared_memory
         fdm = shm_open(path, O_RDWR , 0660);
-        printf("opn_cp_shm %d %d\n", fdm, errno);
+        //printf("opn_cp_shm %d %d\n", fdm, errno);
         if (fdm == -1){
             err_and_leave("Error when creating file-specific sharedmemory", 5);
         }
@@ -237,7 +246,7 @@ int shared_receiver(setting_t settings, int lockfd, mmap_creat_ret_t mmap_info){
     // Here I'm only holding copy->leaving[1]
     FILE* fstr = fopen(settings.filename, "w");
     ftruncate(fileno(fstr), 0);
-    printf("Opened file\n");
+    //printf("Opened file\n");
 
     int to_read = 1;
     int idx = 0;
@@ -251,6 +260,9 @@ int shared_receiver(setting_t settings, int lockfd, mmap_creat_ret_t mmap_info){
             err_and_leave("Error", 5);
         }
         to_read = (n_wr > 0);
+
+        //printf("Read %ld bytes\n", n_wr);
+
         // Lock the leaving lock
         pthread_mutex_lock(&(copy->leaving[idx]));
         // Release active

src/shm/shm.h

@@ -7,8 +7,6 @@
 #include "../shared/types.h"
 #include "../shared/hash.h"
 #include "sync_util.h"
-#define NUM_READERS (2)
-#define DEFAULT_WIDTH (2048)
 #define BASEPATHSHM "/tmp/shm_ocp/"
 #define SHMEMBASE "/ocp_sync"