bc: simpler calling convention for bc_read_file(), bc_program_search()

function                                             old     new   delta
bc_vm_run                                           1854    2020    +166
bc_program_assign                                    482     476      -6
bc_program_pushVar                                   225     215     -10
bc_program_call                                      366     356     -10
bc_program_num                                      1126    1115     -11
bc_program_copyToVar                                 354     343     -11
bc_program_search                                    164     152     -12
bc_program_execStr                                   573     559     -14
bc_program_exec                                     4544    4530     -14
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/8 up/down: 166/-88)            Total: 78 bytes
   text	   data	    bss	    dec	    hex	filename
 988523	    485	   7296	 996304	  f33d0	busybox_old
 988601	    485	   7296	 996382	  f341e	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 23 insertions, 26 deletions

diff --git a/miscutils/bc.c b/miscutils/bc.c
index 25b03a95d..7e72ab28f 100644
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -1386,25 +1386,23 @@ static BcStatus bc_read_line(BcVec *vec, const char *prompt)
         return BC_STATUS_SUCCESS;
 }
 
-static BcStatus bc_read_file(const char *path, char **buf)
+static char* bc_read_file(const char *path)
 {
-        BcStatus s = BC_STATUS_BIN_FILE;
+        char *buf;
         size_t size = ((size_t) -1);
         size_t i;
 
-        *buf = xmalloc_open_read_close(path, &size);
+        buf = xmalloc_open_read_close(path, &size);
 
         for (i = 0; i < size; ++i) {
-                if (BC_READ_BIN_CHAR((*buf)[i]))
-                        goto read_err;
+                if (BC_READ_BIN_CHAR(buf[i])) {
+                        free(buf);
+                        buf = NULL;
+                        break;
+                }
         }
 
-        return BC_STATUS_SUCCESS;
-
-read_err:
-        free(*buf);
-        return s;
-///convert to better return convention
+        return buf;
 }
 
 static void bc_args(int argc, char **argv)
@@ -5275,7 +5273,7 @@ static BcStatus common_parse_expr(BcParse *p, uint8_t flags)
         }
 }
 
-static void bc_program_search(char *id, BcVec **ret, bool var)
+static BcVec* bc_program_search(char *id, bool var)
 {
         BcStatus s;
         BcId e, *ptr;
@@ -5299,8 +5297,7 @@ static void bc_program_search(char *id, BcVec **ret, bool var)
 
         ptr = bc_vec_item(map, i);
         if (new) ptr->name = xstrdup(e.name);
-        *ret = bc_vec_item(v, ptr->idx);
-/// convert to better return convention
+        return bc_vec_item(v, ptr->idx);
 }
 
 static BcStatus bc_program_num(BcResult *r, BcNum **num, bool hex)
@@ -5349,7 +5346,7 @@ static BcStatus bc_program_num(BcResult *r, BcNum **num, bool hex)
                 {
                         BcVec *v;
 
-                        bc_program_search(r->d.id.name, &v, r->t == BC_RESULT_VAR);
+                        v = bc_program_search(r->d.id.name, r->t == BC_RESULT_VAR);
 
                         if (r->t == BC_RESULT_ARRAY_ELEM) {
                                 v = bc_vec_top(v);
@@ -5792,7 +5789,7 @@ static BcStatus bc_program_copyToVar(char *name, bool var)
 
         ptr = bc_vec_top(&G.prog.results);
         if ((ptr->t == BC_RESULT_ARRAY) != !var) return BC_STATUS_EXEC_BAD_TYPE;
-        bc_program_search(name, &v, var);
+        v = bc_program_search(name, var);
 
 #if ENABLE_DC
         if (ptr->t == BC_RESULT_STR && !var) return BC_STATUS_EXEC_BAD_TYPE;
@@ -5803,7 +5800,7 @@ static BcStatus bc_program_copyToVar(char *name, bool var)
         if (s) return s;
 
         // Do this once more to make sure that pointers were not invalidated.
-        bc_program_search(name, &v, var);
+        v = bc_program_search(name, var);
 
         if (var) {
                 bc_num_init(&r.d.n, BC_NUM_DEF_SIZE);
@@ -5841,7 +5838,7 @@ static BcStatus bc_program_assign(char inst)
                 BcVec *v;
 
                 if (left->t != BC_RESULT_VAR) return BC_STATUS_EXEC_BAD_TYPE;
-                bc_program_search(left->d.id.name, &v, true);
+                v = bc_program_search(left->d.id.name, true);
 
                 return bc_program_assignStr(right, v, false);
         }
@@ -5913,7 +5910,7 @@ static BcStatus bc_program_pushVar(char *code, size_t *bgn,
         r.d.id.name = name;
 
 #if ENABLE_DC
-        bc_program_search(name, &v, true);
+        v = bc_program_search(name, true);
         num = bc_vec_top(v);
 
         if (pop || copy) {
@@ -6023,7 +6020,6 @@ static BcStatus bc_program_call(char *code, size_t *idx)
         BcInstPtr ip;
         size_t i, nparams = bc_program_index(code, idx);
         BcFunc *func;
-        BcVec *v;
         BcId *a;
         BcResultData param;
         BcResult *arg;
@@ -6049,9 +6045,10 @@ static BcStatus bc_program_call(char *code, size_t *idx)
         }
 
         for (; i < func->autos.len; ++i) {
+                BcVec *v;
 
                 a = bc_vec_item(&func->autos, i);
-                bc_program_search(a->name, &v, a->idx);
+                v = bc_program_search(a->name, a->idx);
 
                 if (a->idx) {
                         bc_num_init(&param.n, BC_NUM_DEF_SIZE);
@@ -6103,7 +6100,7 @@ static BcStatus bc_program_return(char inst)
                 BcVec *v;
                 BcId *a = bc_vec_item(&f->autos, i);
 
-                bc_program_search(a->name, &v, a->idx);
+                v = bc_program_search(a->name, a->idx);
                 bc_vec_pop(v);
         }
 
@@ -6397,7 +6394,6 @@ static BcStatus bc_program_execStr(char *code, size_t *bgn,
 
         if (cond) {
 
-                BcVec *v;
                 char *name, *then_name = bc_program_name(code, bgn), *else_name = NULL;
 
                 if (code[*bgn] == BC_PARSE_STREND)
@@ -6415,7 +6411,8 @@ static BcStatus bc_program_execStr(char *code, size_t *bgn,
                 }
 
                 if (exec) {
-                        bc_program_search(name, &v, true);
+                        BcVec *v;
+                        v = bc_program_search(name, true);
                         n = bc_vec_top(v);
                 }
 
@@ -7017,8 +7014,8 @@ static BcStatus bc_vm_file(const char *file)
         BcInstPtr *ip;
 
         G.prog.file = file;
-        s = bc_read_file(file, &data);
-        if (s) return bc_vm_error(s, file, 0);
+        data = bc_read_file(file);
+        if (!data) return bc_vm_error(BC_STATUS_BIN_FILE, file, 0);
 
         bc_lex_file(&G.prs.l, file);
         s = bc_vm_process(data);