lscpu: use buffer for data and headers

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/sys-utils/lscpu.c b/sys-utils/lscpu.c
index bd2c073a9e1d357742a6923b4d27edee5d7fd45c..423da0468a66ff7c3fd1b79dbbb639e5056e73c9 100644 (file)
--- a/sys-utils/lscpu.c
+++ b/sys-utils/lscpu.c
@@ -884,58 +884,107 @@ read_nodes(struct lscpu_desc *desc)
                                        i);
 }
 
-static void
-print_parsable_cell(struct lscpu_desc *desc, int cpu, int col,
-                   struct lscpu_modifier *mod)
+static char *
+get_cell_data(struct lscpu_desc *desc, int cpu, int col,
+             struct lscpu_modifier *mod,
+             char *buf, size_t bufsz)
 {
        size_t setsize = CPU_ALLOC_SIZE(maxcpus);
        size_t idx;
-       int j;
+
+       *buf = '\0';
 
        switch (col) {
        case COL_CPU:
-               printf("%d", cpu);
+               snprintf(buf, bufsz, "%d", cpu);
                break;
        case COL_CORE:
                if (cpuset_ary_isset(cpu, desc->coremaps,
                                     desc->ncores, setsize, &idx) == 0)
-                       printf("%zd", idx);
+                       snprintf(buf, bufsz, "%zd", idx);
                break;
        case COL_SOCKET:
                if (cpuset_ary_isset(cpu, desc->socketmaps,
                                     desc->nsockets, setsize, &idx) == 0)
-                       printf("%zd", idx);
+                       snprintf(buf, bufsz, "%zd", idx);
                break;
        case COL_NODE:
                if (cpuset_ary_isset(cpu, desc->nodemaps,
                                     desc->nnodes, setsize, &idx) == 0)
-                       printf("%zd", idx);
+                       snprintf(buf, bufsz, "%zd", idx);
                break;
        case COL_BOOK:
                if (cpuset_ary_isset(cpu, desc->bookmaps,
                                     desc->nbooks, setsize, &idx) == 0)
-                       printf("%zd", idx);
+                       snprintf(buf, bufsz, "%zd", idx);
                break;
        case COL_CACHE:
+       {
+               char *p = buf;
+               size_t sz = bufsz;
+               int j;
+
                for (j = desc->ncaches - 1; j >= 0; j--) {
                        struct cpu_cache *ca = &desc->caches[j];
 
                        if (cpuset_ary_isset(cpu, ca->sharedmaps,
-                                            ca->nsharedmaps, setsize, &idx) == 0)
-                               printf("%zd", idx);
-                       if (j != 0)
-                               putchar(mod->compat ? ',' : ':');
+                                            ca->nsharedmaps, setsize, &idx) == 0) {
+                               int x = snprintf(p, sz, "%zd", idx);
+                               if (x <= 0 || (size_t) x + 2 >= sz)
+                                       return NULL;
+                               p += x;
+                               sz -= x;
+                       }
+                       if (j != 0) {
+                               *p++ = mod->compat ? ',' : ':';
+                               *p = '\0';
+                               sz++;
+                       }
                }
                break;
+       }
        case COL_POLARIZATION:
                if (desc->polarization)
-                       printf("%s", polar_modes[desc->polarization[cpu]].parsable);
+                       snprintf(buf, bufsz, "%s",
+                                polar_modes[desc->polarization[cpu]].parsable);
                break;
        case COL_ADDRESS:
                if (desc->addresses)
-                       printf("%d", desc->addresses[cpu]);
+                       snprintf(buf, bufsz, "%d", desc->addresses[cpu]);
                break;
        }
+       return buf;
+}
+
+static char *
+get_cell_header(struct lscpu_desc *desc, int col,
+               struct lscpu_modifier *mod,
+               char *buf, size_t bufsz)
+{
+       *buf = '\0';
+
+       if (col == COL_CACHE) {
+               char *p = buf;
+               size_t sz = bufsz;
+               int i;
+
+               for (i = desc->ncaches - 1; i >= 0; i--) {
+                       int x = snprintf(p, sz, "%s", desc->caches[i].name);
+                       if (x <= 0 || (size_t) x + 2 > sz)
+                               return NULL;
+                       sz -= x;
+                       p += x;
+                       if (i > 0) {
+                               *p++ = mod->compat ? ',' : ':';
+                               *p = '\0';
+                               sz++;
+                       }
+               }
+               if (desc->ncaches)
+                       return buf;
+       }
+       snprintf(buf, bufsz, colnames[col]);
+       return buf;
 }
 
 /*
@@ -965,8 +1014,12 @@ static void
 print_parsable(struct lscpu_desc *desc, int cols[], int ncols,
               struct lscpu_modifier *mod)
 {
-       int i, c;
+       char buf[BUFSIZ], *data;
+       int i;
 
+       /*
+        * Header
+        */
        printf(_(
        "# The following is the parsable format, which can be fed to other\n"
        "# programs. Each different item in every column has an unique ID\n"
@@ -977,26 +1030,23 @@ print_parsable(struct lscpu_desc *desc, int cols[], int ncols,
                if (cols[i] == COL_CACHE) {
                        if (mod->compat && !desc->ncaches)
                                continue;
-                       if (i > 0)
-                               putchar(',');
                        if (mod->compat && i != 0)
                                putchar(',');
-                       for (c = desc->ncaches - 1; c >= 0; c--) {
-                               printf("%s", desc->caches[c].name);
-                               if (c > 0)
-                                       putchar(mod->compat ? ',' : ':');
-                       }
-                       if (!desc->ncaches)
-                               fputs(colnames[cols[i]], stdout);
-               } else {
-                       if (i > 0)
-                               putchar(',');
-                       fputs(colnames[cols[i]], stdout);
                }
+               if (i > 0)
+                       putchar(',');
+
+               data = get_cell_header(desc, cols[i], mod, buf, sizeof(buf));
+               fputs(data && *data ? data : "", stdout);
        }
        putchar('\n');
 
+       /*
+        * Data
+        */
        for (i = 0; i < desc->ncpus; i++) {
+               int c;
+
                if (desc->online && !is_cpu_online(desc, i))
                        continue;
                for (c = 0; c < ncols; c++) {
@@ -1008,7 +1058,10 @@ print_parsable(struct lscpu_desc *desc, int cols[], int ncols,
                        }
                        if (c > 0)
                                putchar(',');
-                       print_parsable_cell(desc, i, cols[c], mod);
+
+                       data = get_cell_data(desc, i, cols[c], mod,
+                                            buf, sizeof(buf));
+                       fputs(data && *data ? data : "", stdout);
                }
                putchar('\n');
        }