diff options
Diffstat (limited to 'src/xzdec/xzdec.c')
| -rw-r--r-- | src/xzdec/xzdec.c | 74 |
1 files changed, 53 insertions, 21 deletions
diff --git a/src/xzdec/xzdec.c b/src/xzdec/xzdec.c index 09e8817e..e6f576de 100644 --- a/src/xzdec/xzdec.c +++ b/src/xzdec/xzdec.c @@ -96,8 +96,7 @@ help(void) " -d, --decompress (ignored)\n" " -k, --keep (ignored)\n" " -f, --force (ignored)\n" -" -M, --memory=NUM use NUM bytes of memory at maximum (0 means default);\n" -" the suffixes k, M, G, Ki, Mi, and Gi are supported.\n" +" -M, --memory=NUM use NUM bytes of memory at maximum (0 means default)\n" " -q, --quiet specify *twice* to suppress errors\n" " -Q, --no-warn (ignored)\n" " -h, --help display this help and exit\n" @@ -125,39 +124,54 @@ version(void) } -/// Finds out the amount of physical memory in the system, and sets -/// a default memory usage limit. +/// Find out the amount of physical memory (RAM) in the system, and set +/// the memory usage limit to the given percentage of RAM. static void -set_default_memlimit(void) +memlimit_set_percentage(uint32_t percentage) { - const uint64_t mem = physmem(); + uint64_t mem = physmem(); + // If we cannot determine the amount of RAM, assume 32 MiB. if (mem == 0) - // Cannot autodetect, use 10 MiB as the default limit. - memlimit = UINT64_C(10) * 1024 * 1024; + mem = UINT64_C(32) * 1024 * 1024; + + memlimit = percentage * mem / 100; + return; +} + + +/// Set the memory usage limit to give number of bytes. Zero is a special +/// value to indicate the default limit. +static void +memlimit_set(uint64_t new_memlimit) +{ + if (new_memlimit == 0) + memlimit_set_percentage(40); else - // Limit is 40 % of RAM. - memlimit = mem * 2 / 5; + memlimit = new_memlimit; return; } -/// \brief Converts a string to uint64_t +/// \brief Convert a string to uint64_t /// /// This is rudely copied from src/xz/util.c and modified a little. :-( /// +/// \param max Return value when the string "max" was specified. +/// static uint64_t -str_to_uint64(const char *value) +str_to_uint64(const char *value, uint64_t max) { uint64_t result = 0; // Accept special value "max". if (strcmp(value, "max") == 0) - return UINT64_MAX; + return max; if (*value < '0' || *value > '9') { - my_errorf("%s: Not a number", value); + my_errorf("%s: Value is not a non-negative decimal integer", + value); exit(EXIT_FAILURE); } @@ -247,12 +261,30 @@ parse_options(int argc, char **argv) case 'Q': break; - case 'M': - memlimit = str_to_uint64(optarg); - if (memlimit == 0) - set_default_memlimit(); + case 'M': { + // Support specifying the limit as a percentage of + // installed physical RAM. + const size_t len = strlen(optarg); + if (len > 0 && optarg[len - 1] == '%') { + // Memory limit is a percentage of total + // installed RAM. + optarg[len - 1] = '\0'; + const uint64_t percentage + = str_to_uint64(optarg, 100); + if (percentage < 1 || percentage > 100) { + my_errorf("Percentage must be in " + "the range [1, 100]"); + exit(EXIT_FAILURE); + } + + memlimit_set_percentage(percentage); + } else { + memlimit_set(str_to_uint64( + optarg, UINT64_MAX)); + } break; + } case 'q': if (display_errors > 0) @@ -416,9 +448,9 @@ main(int argc, char **argv) // error and help messages. argv0 = argv[0]; - // Detect amount of installed RAM and set the memory usage limit. - // This is needed before parsing the command line arguments. - set_default_memlimit(); + // Set the default memory usage limit. This is needed before parsing + // the command line arguments. + memlimit_set(0); // Parse the command line options. parse_options(argc, argv); |