| #include <net-snmp/net-snmp-config.h> |
| #include <net-snmp/net-snmp-includes.h> |
| #include <net-snmp/agent/net-snmp-agent-includes.h> |
| #include <net-snmp/agent/hardware/memory.h> |
| |
| #include <unistd.h> |
| #include <fcntl.h> |
| |
| /* |
| * Try to use an initial size that will cover default cases. We aren't talking |
| * about huge files, so why fiddle about with reallocs? |
| * I checked /proc/meminfo sizes on 3 different systems: 598, 644, 654 |
| * |
| * On newer systems, the size is up to around 930 (2.6.27 kernel) |
| * or 1160 (2.6.28 kernel) |
| */ |
| #define MEMINFO_INIT_SIZE 1279 |
| #define MEMINFO_STEP_SIZE 256 |
| #define MEMINFO_FILE "/proc/meminfo" |
| |
| /* |
| * Load the latest memory usage statistics |
| */ |
| int netsnmp_mem_arch_load( netsnmp_cache *cache, void *magic ) { |
| int statfd; |
| static char *buff = NULL; |
| static int bsize = 0; |
| static int first = 1; |
| ssize_t bytes_read; |
| char *b; |
| unsigned long memtotal = 0, memfree = 0, memshared = 0, |
| buffers = 0, cached = 0, |
| swaptotal = 0, swapfree = 0; |
| |
| netsnmp_memory_info *mem; |
| |
| /* |
| * Retrieve the memory information from the underlying O/S... |
| */ |
| if ((statfd = open(MEMINFO_FILE, O_RDONLY, 0)) == -1) { |
| snmp_log_perror(MEMINFO_FILE); |
| return -1; |
| } |
| if (bsize == 0) { |
| bsize = MEMINFO_INIT_SIZE; |
| buff = malloc(bsize+1); |
| if (NULL == buff) { |
| snmp_log(LOG_ERR, "malloc failed\n"); |
| close(statfd); |
| return -1; |
| } |
| } |
| while ((bytes_read = read(statfd, buff, bsize)) == bsize) { |
| b = realloc(buff, bsize + MEMINFO_STEP_SIZE + 1); |
| if (NULL == b) { |
| snmp_log(LOG_ERR, "malloc failed\n"); |
| close(statfd); |
| return -1; |
| } |
| buff = b; |
| bsize += MEMINFO_STEP_SIZE; |
| DEBUGMSGTL(("mem", "/proc/meminfo buffer increased to %d\n", bsize)); |
| close(statfd); |
| statfd = open(MEMINFO_FILE, O_RDONLY, 0); |
| if (statfd == -1) { |
| snmp_log_perror(MEMINFO_FILE); |
| return -1; |
| } |
| } |
| close(statfd); |
| if (bytes_read <= 0) { |
| snmp_log_perror(MEMINFO_FILE); |
| } else { |
| buff[bytes_read] = '\0'; |
| } |
| |
| /* |
| * ... parse this into a more useable form... |
| */ |
| b = strstr(buff, "MemTotal: "); |
| if (b) |
| sscanf(b, "MemTotal: %lu", &memtotal); |
| else { |
| if (first) |
| snmp_log(LOG_ERR, "No MemTotal line in /proc/meminfo\n"); |
| } |
| b = strstr(buff, "MemFree: "); |
| if (b) |
| sscanf(b, "MemFree: %lu", &memfree); |
| else { |
| if (first) |
| snmp_log(LOG_ERR, "No MemFree line in /proc/meminfo\n"); |
| } |
| if (0 == netsnmp_os_prematch("Linux","2.4")) { |
| b = strstr(buff, "MemShared: "); |
| if (b) |
| sscanf(b, "MemShared: %lu", &memshared); |
| else if (first) |
| snmp_log(LOG_ERR, "No MemShared line in /proc/meminfo\n"); |
| } |
| else { |
| b = strstr(buff, "Shmem: "); |
| if (b) |
| sscanf(b, "Shmem: %lu", &memshared); |
| else if (first) |
| snmp_log(LOG_ERR, "No Shmem line in /proc/meminfo\n"); |
| } |
| b = strstr(buff, "Buffers: "); |
| if (b) |
| sscanf(b, "Buffers: %lu", &buffers); |
| else { |
| if (first) |
| snmp_log(LOG_ERR, "No Buffers line in /proc/meminfo\n"); |
| } |
| b = strstr(buff, "Cached: "); |
| if (b) |
| sscanf(b, "Cached: %lu", &cached); |
| else { |
| if (first) |
| snmp_log(LOG_ERR, "No Cached line in /proc/meminfo\n"); |
| } |
| b = strstr(buff, "SwapTotal: "); |
| if (b) |
| sscanf(b, "SwapTotal: %lu", &swaptotal); |
| else { |
| if (first) |
| snmp_log(LOG_ERR, "No SwapTotal line in /proc/meminfo\n"); |
| } |
| b = strstr(buff, "SwapFree: "); |
| if (b) |
| sscanf(b, "SwapFree: %lu", &swapfree); |
| else { |
| if (first) |
| snmp_log(LOG_ERR, "No SwapFree line in /proc/meminfo\n"); |
| } |
| first = 0; |
| |
| |
| /* |
| * ... and save this in a standard form. |
| */ |
| mem = netsnmp_memory_get_byIdx( NETSNMP_MEM_TYPE_PHYSMEM, 1 ); |
| if (!mem) { |
| snmp_log_perror("No Physical Memory info entry"); |
| } else { |
| if (!mem->descr) |
| mem->descr = strdup("Physical memory"); |
| mem->units = 1024; |
| mem->size = memtotal; |
| mem->free = memfree; |
| mem->other = -1; |
| } |
| |
| mem = netsnmp_memory_get_byIdx( NETSNMP_MEM_TYPE_VIRTMEM, 1 ); |
| if (!mem) { |
| snmp_log_perror("No Virtual Memory info entry"); |
| } else { |
| if (!mem->descr) |
| mem->descr = strdup("Virtual memory"); |
| mem->units = 1024; |
| mem->size = memtotal+swaptotal; |
| mem->free = memfree +swapfree; |
| mem->other = -1; |
| } |
| |
| mem = netsnmp_memory_get_byIdx( NETSNMP_MEM_TYPE_SHARED, 1 ); |
| if (!mem) { |
| snmp_log_perror("No Shared Memory info entry"); |
| } else { |
| if (!mem->descr) |
| mem->descr = strdup("Shared memory"); |
| mem->units = 1024; |
| mem->size = memshared; |
| mem->free = 0; /* All in use */ |
| mem->other = -1; |
| } |
| |
| mem = netsnmp_memory_get_byIdx( NETSNMP_MEM_TYPE_CACHED, 1 ); |
| if (!mem) { |
| snmp_log_perror("No Cached Memory info entry"); |
| } else { |
| if (!mem->descr) |
| mem->descr = strdup("Cached memory"); |
| mem->units = 1024; |
| mem->size = cached; |
| mem->free = 0; /* Report cached size/used as equal */ |
| mem->other = -1; |
| } |
| |
| mem = netsnmp_memory_get_byIdx( NETSNMP_MEM_TYPE_SWAP, 1 ); |
| if (!mem) { |
| snmp_log_perror("No Swap info entry"); |
| } else { |
| if (!mem->descr) |
| mem->descr = strdup("Swap space"); |
| mem->units = 1024; |
| mem->size = swaptotal; |
| mem->free = swapfree; |
| mem->other = -1; |
| } |
| |
| mem = netsnmp_memory_get_byIdx( NETSNMP_MEM_TYPE_MBUF, 1 ); |
| if (!mem) { |
| snmp_log_perror("No Buffer, etc info entry"); |
| } else { |
| if (!mem->descr) |
| mem->descr = strdup("Memory buffers"); |
| mem->units = 1024; |
| mem->size = memtotal; /* Traditionally we've always regarded |
| all memory as potentially available |
| for memory buffers. */ |
| mem->free = memtotal - buffers; |
| mem->other = -1; |
| } |
| |
| return 0; |
| } |
