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view lwasm/section.c @ 264:346966cffeef
Clean up various warnings when building under -Wall
Add some gimmicks to prevent fread() and fwrite() warnings about ignoring
the return value. Yes, this is probably not a good thing to do, but doing
something with a non-success return value is going to involve crashing out
or something anyway.
Also fix several warnings about variables used while possibly uninitialized.
The code flow shows that this cannot be the case but initializing them to a
plausible value at declaration time costs pretty much nothing and it makes
gcc happy.
Also caught a use of | instead of || which probably would have caused a
certain check for duplicate declarations in __os9 sections to behave oddly.
author | William Astle <lost@l-w.ca> |
---|---|
date | Wed, 06 Feb 2013 21:43:10 -0700 |
parents | 35f7ce3ef857 |
children | 8764142b3192 |
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/* section.c Copyright © 2010 William Astle This file is part of LWTOOLS. LWTOOLS is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <string.h> #include <ctype.h> #include <lw_string.h> #include <lw_alloc.h> #include "lwasm.h" #include "instab.h" PARSEFUNC(pseudo_parse_section) { char *p2; char *sn; char *opts = NULL; sectiontab_t *s; if (as -> output_format != OUTPUT_OBJ) { lwasm_register_error(as, l, "Cannot use sections unless using the object target"); return; } if (!**p) { lwasm_register_error(as, l, "Need section name"); return; } l -> len = 0; if (as -> csect) { lw_expr_destroy(as -> csect -> offset); as -> csect -> offset = lw_expr_copy(l -> addr); as -> csect = NULL; } for (p2 = *p; *p2 && *p2 != ',' && !isspace(*p2); p2++) /* do nothing */ ; sn = lw_strndup(*p, p2 - *p); *p = p2; if (**p == ',') { // have opts (*p)++; for (p2 = *p; *p2 && !isspace(*p2); p2++) /* do nothing */ ; opts = lw_strndup(*p, p2 - *p); *p = p2; } for (s = as -> sections; s; s = s -> next) { if (!strcmp(s -> name, sn)) break; } if (s && opts) { lwasm_register_warning(as, l, "Section flags can only be specified the first time; ignoring duplicate definition"); } if (!s) { // create section data structure s = lw_alloc(sizeof(sectiontab_t)); s -> oblen = 0; s -> obsize = 0; s -> obytes = NULL; s -> name = lw_strdup(sn); s -> offset = lw_expr_build(lw_expr_type_special, lwasm_expr_secbase, s); s -> flags = section_flag_none; s -> reloctab = NULL; if (!strcasecmp(sn, "bss") || !strcasecmp(sn, ".bss")) { s -> flags |= section_flag_bss; } if (!strcasecmp(sn, "_constant") || !strcasecmp(sn, "_constants")) { s -> flags |= section_flag_constant; } // parse options if (opts) { // only one option ("bss" or "!bss") if (!strcasecmp(opts, "bss")) { s -> flags |= section_flag_bss; } else if (!strcasecmp(opts, "!bss")) { s -> flags &= ~section_flag_bss; } else if (!strcasecmp(opts, "constant")) { s -> flags |= section_flag_constant; } else if (!strcasecmp(opts, "!constant")) { s -> flags |= section_flag_constant; } else { lwasm_register_error(as, l, "Unrecognized section flag"); lw_free(sn); lw_free(opts); lw_free(s -> name); lw_expr_destroy(s -> offset); lw_free(s); return; } } s -> next = as -> sections; as -> sections = s; } // cause all instances of "constant" sections to start at 0 if (s -> flags & section_flag_constant) s -> offset = lw_expr_build(lw_expr_type_int, 0); lw_expr_destroy(l -> addr); l -> addr = lw_expr_copy(s -> offset); lw_expr_destroy(l -> daddr); l -> daddr = lw_expr_copy(s -> offset); as -> csect = s; as -> context = lwasm_next_context(as); l -> len = 0; lw_free(opts); lw_free(sn); } PARSEFUNC(pseudo_parse_endsection) { if (as -> output_format != OUTPUT_OBJ) { lwasm_register_error(as, l, "Cannot use sections unless using the object target"); return; } l -> len = 0; if (!(as -> csect)) { lwasm_register_error(as, l, "ENDSECTION without SECTION"); return; } // save offset in case another instance of the section appears lw_expr_destroy(as -> csect -> offset); as -> csect -> offset = l -> addr; // reset address to 0 l -> addr = lw_expr_build(lw_expr_type_int, 0); as -> csect = NULL; // end of section is a context break as -> context = lwasm_next_context(as); skip_operand(p); } PARSEFUNC(pseudo_parse_export) { int after = 0; char *sym = NULL; exportlist_t *e; if (as -> output_format != OUTPUT_OBJ) { lwasm_register_error(as, l, "EXPORT only supported for object target"); return; } l -> len = 0; if (l -> sym) { sym = lw_strdup(l -> sym); l -> symset = 1; } if (l -> sym) { skip_operand(p); } again: if (after || !sym) { char *p2; after = 1; for (p2 = *p; *p2 && *p2 != ',' && !isspace(*p2); p2++) /* do nothing */ ; sym = lw_strndup(*p, p2 - *p); *p = p2; } if (!sym) { lwasm_register_error(as, l, "No symbol for EXPORT"); return; } // add the symbol to the "export" list (which will be resolved // after the parse pass is complete e = lw_alloc(sizeof(exportlist_t)); e -> next = as -> exportlist; e -> symbol = lw_strdup(sym); e -> line = l; e -> se = NULL; as -> exportlist = e; lw_free(sym); if (after && **p == ',') { (*p)++; for (; **p && isspace(**p); (*p)++) /* do nothing */ ; goto again; } } PARSEFUNC(pseudo_parse_extern) { int after = 0; char *sym = NULL; importlist_t *e; if (as -> output_format != OUTPUT_OBJ) { lwasm_register_error(as, l, "IMPORT only supported for object target"); return; } l -> len = 0; if (l -> sym) { sym = lw_strdup(l -> sym); l -> symset = 1; } if (l -> sym) { skip_operand(p); } again: if (after || !sym) { char *p2; after = 1; for (p2 = *p; *p2 && *p2 != ',' && !isspace(*p2); p2++) /* do nothing */ ; sym = lw_strndup(*p, p2 - *p); *p = p2; } if (!sym) { lwasm_register_error(as, l, "No symbol for IMPORT"); return; } // add the symbol to the "export" list (which will be resolved // after the parse pass is complete e = lw_alloc(sizeof(importlist_t)); e -> next = as -> importlist; e -> symbol = lw_strdup(sym); as -> importlist = e; lw_free(sym); if (after && **p == ',') { (*p)++; for (; **p && isspace(**p); (*p)++) /* do nothing */ ; goto again; } } PARSEFUNC(pseudo_parse_extdep) { int after = 0; char *sym = NULL; // importlist_t *e; if (as -> output_format != OUTPUT_OBJ) { lwasm_register_error(as, l, "EXTDEP only supported for object target"); return; } if (!as -> csect) { lwasm_register_error(as, l, "EXTDEP must be within a section"); return; } l -> len = 0; if (l -> sym) sym = lw_strdup(l -> sym); if (l -> sym) { skip_operand(p); } again: if (after || !sym) { char *p2; after = 1; for (p2 = *p; *p2 && *p2 != ',' && !isspace(*p2); p2++) /* do nothing */ ; sym = lw_strndup(*p, p2 - *p); } if (!sym) { lwasm_register_error(as, l, "No symbol for EXTDEP"); return; } // create a zero-width dependency { lw_expr_t e; e = lw_expr_build(lw_expr_type_int, 0); lwasm_emitexpr(l, e, 0); lw_expr_destroy(e); } if (after && **p == ',') { (*p)++; for (; **p && isspace(**p); (*p)++) /* do nothing */ ; goto again; } }